Gravity – Science for Kids

gravity

At this week’s class we talked about Force, Magnets, and Gravity.

Hands-On Exploration of Gravity

Slide: We set up our climber and slide. The slide is a great way to learn about gravity! It’s really easy to slide down, and sliding up just doesn’t work.

Pulley: We mounted a pulley on the slide, a callback to when we studied Simple Machines last quarter. They could clearly see that if they filled the basket up top, and then let go of the rope, gravity would carry it down to the ground with no effort on their part. If they wanted to raise the basket back up, they had to work (use force) to haul it back up.

Gravitational Impact Testing: Next to the slide, we placed a tub full of Kinetic Sand. (Last year, we had it in a tub on a drop cloth. This year, we put the sand inside a gallon ziplock… but, of course, we had a child open the ziplock, so we probably had the same amount of spillage with both methods.) We put out a wide variety of light and heavy objects. Kids climbed to the slide platform, then dropped an object into the sand to see if it left a mark, what shape the mark was, and how deep the impact crater was. (Safety pointer: kids on the ground love to look at the craters, and lean over for close examination – it’s important that the kids on the platform know to wait for all heads to be clear before they drop the next object! None of our objects were heavy enough to injure, but they might have stung if they hit someone.)

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Marble mazeIMG_20151212_131922536These building toys offer great tinkering opportunities. Kids build, notice problems, re-build, test, decide to re-build to make it taller, and so on. I especially like our set, which is from Discovery Toys, because it includes a gravity well, a launch track where you can load 6 – 12 marbles, then dump them in all at once, and other fun details.

I did learn something important – I’d originally put this on a table top so it would be easy to build and watch the marbles roll down. But, what I hadn’t taken into account was that for small children, it was then hard to reach the top to drop a marble in. So, the kids climbed on the table to reach the top! (OK, it was my kid was doing that… )  So, we moved it to the floor.

This year, we moved the marble maze into the water tub, and let kids pour water beads and water through it. They’ve played with the marble maze before, and played with water beads, so it was fun to combine the two.

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Magnetic ball wall: Based on that standard children’s museum activity, this marble maze is a DIY project (learn how here) using PVC pipes mounted on magnets, stuck to metal oil drip pans, and shooter marbles to run through it. Again, it’s a great tinkering toy – especially because after you finally get everything lined up just right, you’ll run three or four marbles through successfully, then marble #5 bumps something just slightly out of alignment and a marble gets stuck, or marble #6 really knocks it out of line and marbles fall and you have to re-build. We also set up the maze pieces on our metal slide (see photo in magnet post.)

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Gravity well: At many science museums and children’s museums and such, they have a donation bucket where you drop a coin in and it circles around and around and around before finally spiraling down. (The gravity pulls the ball down, but the momentum of the spin slows that fall.) This is an example of centripetal force, as it spins in toward the center.

We invented a mini gravity well with a colander and a shooter marble. You could just use those two items – we added a rubber mat into the center to make it more obvious when it reached the center (because the sound stops as well as the motion). Kids have to learn how to hold it and move it just right to get the ball to spin, so it’s also a chance to learn a new motor skill. Check it out:

Art – Salad Spinner. Prep – cut circles of paper, fill squirt bottles with paint. In class: kids place paper in bottom of spinner basket. Squirt some paint in the middle of the paper. Put the lid on and spin it! Centrifugal force pushes the paint toward the outside of the paper.

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Building Project: Centrifugal Force Air Ship

Materials: paper bowls or plastic cups, string, scissors, hole punch, and optional materials to decorate ship with. Plus small “passengers” for the ship – could use pompoms or small plastic animals, or whatever you have.

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Directions:

  1. Punch holes in the cups or bowls, attach 3–4 lengths of yarn and tie them together.
  2. Fill the ‘ship’ with 5-7 objects as ‘passengers’
  3. Start swinging the ‘ship’ around until it can go over your head and see if you’re able to keep passengers in your Centrifugal Force Ship – “CFS

Note: again, kids are also learning a motor skill with this activity. They had to learn how to start swinging the ship slowly, then faster, then up over their head to keep the pompom in. If you don’t want to have kids build these as a project, it would also be easy to make up a couple before class just for them to play with at outside time.

Learn about the science: http://sciencenetlinks.com/afterschool-resources/fun-forces/

Pendulum painting: I want to do pendulum painting, as described on Handmade Kids Art, Martha Stewart, Growing a Jeweled Rose, Teach Preschool and Science World. I thought it would be a good fit for gravity week, as it ties into centrifugal and centripetal force.

Last week, I made a seismograph for earthquake week. I had an inspiration – could I re-purpose this for pendulum painting this week??

I unfortunately didn’t have time to test the idea before class. When I tested it in class, it failed. I tried to tape over the hole on the bottle while I filled it, and then take off the tape to spin it. At first, the paint was too thick, and wouldn’t come through the hole. But then when I watered it down, it was too thin, and ran out even when the tape was supposedly covering the hole.

I’ll try again next time, when I have time to test it. I think I will build a frame with PVC pipe. I think I will follow Jeweled Rose’s lead and will use a Gatorade bottle or water bottle with a sipping lid – the kind that you can push closed and pull open. Then I can cut the bottom off the bottle, mount it on the pendulum, and refill it as we go along.

Circle Time

After the children have had time to explore all the activities, we gather for circle to give them the conceptual framework of the day, then we send them out to explore all the activities again, with these new ideas.

Big Idea: The key ideas I wanted to convey were that gravity is an invisible force. You can’t see it, but you can see how it affects other things. Gravity pulls toward the center of the earth, so when you drop things, they fall down. You can use energy to jump into the air, but then gravity pulls you back to the ground. (In the Next Generation Science Standards, gravity appears in third grade, under 3-PS2-1, where it simply notes “assessment is limited to gravity… as a force that pulls objects down.”)

Song: We had sung a fun song to the tune of Have you Ever Seen a Lassie for Magnet week, so I wrote a gravity song to that tune. On Magnets, we swayed left and right when singing the words “this way and that way.” For this song, we stood up. When it said “pull this way” we crouched down, and when it says “not that way”, we stood on our toes.

Well, you’ll never see gravity, gravity, gravity
But you can see gravity pull this way, not that.
Chorus: Pull this way, not that way, pull this way, not that way.
You can see gravity pull this way, not that.
You toss up a ball, gravity makes it fall
Oh, you can see gravity pull things to the ground.
(Chorus)
You throw up a gown, gravity brings it back down
Oh, you can see gravity pull things to the ground.
(Chorus)

There’s an alternate gravity song here.

Discussion: I started this circle with the discussion described in the Force post, where I set a block on the table, and asked if I could move it with my mind, or order it to move. The kids guided me through applying force by pushing and pulling. Then, I asked “What if I want to move the block to the ground? Do I have to hold it in my hand and PUSH it down to the ground? Now? I can just nudge it over the edge and it will fall down?? Why? Yes, there’s an invisible force called gravity that pulls things to the ground, or as close to the ground as it can get. When the block was on the table, it was trying hard to get to the ground, but it couldn’t pass through the table, so it laid on the table. When I hold it up in the air like this, then let go, it can pass through the air, so it falls down to the ground.

Book: Then I read I Fall Down (see below) which includes several demos like tossing balls, keys, and more up in the air and watching them fall back down, having a dropping race, first with a penny and a block, then with the block and a feather, then using a bar of soap and a dry sponge to show that things fall at the same rate, but that heavier things fall harder and you feel that harder impact on your hand.

Optional demo: You could tie a whiteboard eraser (or other soft object with a little mass) to a string, and spin it over your head. Explain that you’re the earth, the eraser is the moon, and the string is the force of gravity that prevents the moon from escaping earth’s orbit.

Books

    • I Fall Down is another fabulous book by Vicki Cobb. It does a great job of clearly explaining to 3 – 6 year olds the basics of gravity with lots of hands-on examples of experiments they can do with materials they have at home.
    • Gravity Is a Mystery by Branley. A good option for 6 – 8 year olds. It has enough detail that it might be better to use as a second or third book about gravity, not the first introduction. It goes into details like that gravity pulls you toward the center of the earth, what would happen if you dug a hole through the earth, and about how much gravity there is on other planets.
    • What Is Gravity? by Trumbauer. Ages 3 to 5, good photographs, situations that are relatable for kids like going on a swing or sliding down a slide or apples falling from trees. Conveys basic concept that things that go up come back down because of gravity and that heavier things are pulled on more by gravity. Does not address pull toward earth.  A really solid read-aloud non-fiction for preschool – just not as good as I Fall Down.
    • Why Can’t I Jump Very High? A Book About Gravity by Prasad. Best for 8 – 10 year olds. Really wordy, and covers a LOT of concepts: starts with kids asking why they can’t jump higher in basketball. Covers gravity on earth, gravity on the moon, Aristotle and Newton, drop tests, air resistance and friction.
    • Gravity by Chin. This is a picture book. It has beautiful illustrations and really sets a tone and mood. There are just a few words on each page – the complete words in the main text of the book are: “Gravity makes objects fall to Earth. Without gravity, everything would float away. The moon would drift away from the Earth. The Earth would drift away from the sun. Luckily, everything has gravity. Massive things have a lot of gravity and their gravity pulls on some other things. Gravity keeps the earth near the sun, the moon near the earth, and makes objects fall to earth.” Then on the last two pages of the book, there’s additional info on gravity, mass, weight, and that gravity is weaker with distance.

Preview or Review Videos: Intro to force and gravity: www.youtube.com/watch?v=LEs9J2IQIZY Schoolhouse Rock on gravity: www.youtube.com/watch?v=yHFtk6Si0Fk. Search on YouTube for Bill Nye gravity. There’s also a Sid the Science Kid on gravity… find the transcript here – just click on “full text” – https://www.speakaboos.com/story/sid-the-science-kid-gravity-and-weightlessness.

Follow-Ups: For “homework” – here are some things parents could do with their kids to reinforce the ideas learned in class.

  • Talk about what would happen if there was no gravity.
  • Perhaps watch videos that show astronauts floating in space, and talk about what that would be like. (Go to YouTube and search for “NASA zero gravity”).
  • Play with dropping objects to show that they fall at the same rate… if kids notice that feathers or flat pieces of paper fall slowly, then discuss that this is due to them being caught on air currents, not because gravity works differently for them.
  • Look for more gravity ideas here: http://www.stirthewonder.com/gravity-lab/

 

 

Magnets – Science for Kids

magnets

This week at Inventors’ Lab, we studied force, gravity, and magnets. All of these are easy to explore hands-on, and AFTER the kids have had a chance to explore them, we talk about the theory behind what they’ve observed, then give them more chances to test it.

Hands-On Exploration of Magnets

Simple magnets in action: On a table, we had magnets and metal washers where they could play with the bare bones concept of: magnets pick up metal objects.

Magnetic and non-magnetic objects: We had this really cool makeup case with clear plastic walls, which we filled with magnetic and non-magnetic items. Kids could use magnet wands up the side of the case to see which materials a magnet will pick up. If you don’t have the case, water bottles work just fine! Fill them with objects like beans, rice, washers, paper clips, and plastic toys. These were out on a table with magnetic wands.

(Since we had younger kids, we stuck to a simplistic idea that magnets stick to metal. If you have older kids, you might have aluminum cans and steel cans and explain that magnets only stick to some metals – iron, nickel, cobalt, etc.)

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You could also include magnetic and non-magnetic surfaces and decorative magnets to put on them. For example, a magnetized white board, a cork bulletin board, a wood plank, a steel can and a plastic bottle.

Sorting: We had a pie pan full of objects that they could test and then sort into magnetic or non-magnetic.

What materials can magnetic force reach through? Put out paper clips and several containers, made of paper, glass, plastic, ceramic, wood, and so on. If you put a paper clip inside that container, can the magnet still attract it?

Using magnets to attract hidden objects: We filled the sensory tub with rice or lentils, then buried lots of plastic discs with metal rims, mini clothes pins and other objects that magnets would pick up. Kids could stir a magnet wand around in the rice, then lift it up to see what it had attracted.

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Exploring magnetic poles: We had a container filled with mineral oil and shredded steel wool. Kids could use a bar magnet with it to observe where the metal lined up – this shows where the poles are on the ends of the magnet. This wasn’t as effective as we’d hoped. You can also buy containers filled with iron filings or with iron filings and sand that allow kids to explore how magnetic fields can move pieces of metal.

More on magnetic poles: Have various magnets that will attract and repel each other, and have a “push-pull” table. Challenge them to find ways to use the magnets to pull toward each other (attract) or push away (repel.) We had one pair of magnets that if you held the round magnet one way, it would pull itself down onto the square magnet, but if you held it the other way, the square magnet would push it away. You can put out two Wooden Train Cars and show that if you push them together one way, they connect… if you push them together the other way, they repel. I also like these science toys where there are disc magnets you mount on a post, and the magnets can “float” above each other. (Note: it’s fun to use the magnet balls with the posts from this toy – they’ll roll in circles around the base, or if you have two of them, they’ll chase each other in circles around the base.)

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Magnet Marbles: We had a big collection of Magnetic Marbles for them to chain together and explore.

Magna-tiles: These clear magnetic building blocks are lots of fun to play with. We often use them on the light table.

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Magnetic poetry – you can put out kids’ magnetic poetry sets for some literacy play.

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Art project: You could easily make any art project and mount on a magnet for them to take home and stick on fridge.

You could also make a project where you draw a picture on a paper plate, make a small drawing and put a paper clip or metal brad on it, then use a magnet wand below the plate to pull the object around…. examples of this include making a paper car to drive around a track or make paper ants to move around a plate of “food.” Or make a paper fish, put a magnet strip on it, set it on a piece of blue paper, then use a magnet underneath the paper to move it around.

Experiment exploring magnetic poles – Make Your Own Magnet and/or Compass

Although most of our class’ activity stations are intended for kids to be able to do independently; however, we often have one where we station an adult there to walk kids through a more complicated project or concept exploration. This was our process for this class to help them explore magnets and compasses.

Materials needed: a strong magnet (a weak one like the bar magnet shown in the picture below won’t work to magnetize a paperclip), paperclips, cork rafts like we made in wind week (or other floating object), compass, container of water

  1. Test your magnet: Is it magnetic—will it attract a paper clip?
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  2. Test your paper clip: Is it magnetic—will it attract another paper clip?
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  3. (optional: Unfold your paperclip.) Take the magnet, rub it down the length of the paperclip, always moving in the same direction, for 40 or 50 strokes. Count out loud to keep track. (This helps all the iron particles in the paper clip line up in the same direction.)
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  4. Test your paper clip: Now is it magnetic—now will it attract another clip?
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  5. Test your magnet as a compass. Set it on the raft, then spin the raft, and wait for it to stop spinning. Is the north end of the magnet facing north? (Check the compass to see what direction is north.)
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  6. Now, test your magnetized paper clip as a compass. Set it on the small raft, then spin the raft. Wait for it to stop spinning. Is the magnetized end pointing north? If not, try rubbing the magnet on it again to recharge the magnetism.
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Circle Time

Grounding in Experience: Ask “Before class today, who had used a magnet? Where? What for?” They may talk about refrigerator magnets, magnetic toys, etc. “What do magnets stick to? What won’t they stick to?”

You can also use a magnet and ask them – will it stick to the white board? Will it stick to this wooden desk? Will it stick to the lamp?

Demo: Show two bar magnets that are clearly marked with north and south poles. Show how if you put opposite ends next to each other, they attract – they pull together. If you put matching ends together, they repel, or push away. (You can also demo this with other magnets – it’s great if you have one that’s has a strong enough magnetic field that you don’t even have to touch them together… it can lift another magnet up in the air (levitate it) to pull them together. This relates to Next Generation Science Standard 3-PS2.3Emphasize that magnets can push or pull other magnets.

Song: From www.tooter4kids.com/Magnets/magnet_poems.htm. To the tune of Did you ever see a Lassie? Have them lean side to side when singing “this way and that”

  1. Did you ever see a magnet, a magnet, a magnet? Did you ever see a magnet pull this way and that?
    Chorus: Pull this way and that way, and this way and that way. Did you ever see a magnet pull this way and that?
  2. On iron and steel, its pull is unreal! Did you ever see a magnet pull this way and that? Chorus
  3. A magnet has action, it’s called an attraction! Did you ever see a magnet pull this way and that? Chorus

Alternate song: https://www.musick8.com/html/current_tune.php?numbering=101&songorder=13

Magnets push, magnets pull
Magnets stick to certain metals – like iron
Magnets can stick to each other
And push each other away
(Repeat)
Push and pull, push and pull
That’s what magnets do
Push and pull, push and pull
That’s what magnets do

Books

  • Magnets by Nelson. An easy read-aloud non-fiction book appropriate for preschool kids, age 3 – 5. Clear photographs of items that would be familiar to a young child.
  • Magnets by Royston and Magnets Push, Magnets Pull by Weakland. Nice basic non-fiction overviews, with nice photos and clear examples, appropriate for ages 5 – 7. I prefer Royston, just because Weakland gives some examples (like motors, speakers, and MRI machines) that would be hard for young kids to grasp how they relate to the basics of magnetism we’re talking about in class.
  • What Makes a Magnet? by Branley. For ages 6 – 8. Nice overview, but if you read it, the kids will want to do all the activities described, so be prepared. They include: making a box of miscellaneous items, then tying a magnet on a string and going “fishing”, magnetizing a needle, building a floating compass with the needle and two corks, and a magnetic technology scavenger hunt checklist.
  • Science Experiments With Magnets by Kuskowski, Experiments with Magnets and Metals by Taylor-Butler, and Step-by-Step Experiments with Magnets by Hagler are all aimed at 1st-3rd graders, and all include a good collection of experiment ideas with clear photographic instructions. Any would be fine supplements to class. Kuskowski is my favorite and includes a few experiments that I have not described here.

Demo: If you have recently studied Gravity, this is a fun demo to do, from Buggy and Buddy. Prep: Tie a paper clip to a string, then tie the string to a wood dowel. Make two towers of Duplos as tall as the string is long. Stick a strong magnet to a metal ruler and “bridge” it between the Duplo towers.

Then, in class: hold up the dowel. Ask “where does the paper clip hang?” (Straight down.) “Why?” (Gravity.) Tilt the dowel – “which way does the clip hang?” (Down.) “Can anything pull it back up? I can pull it up with my fingers – that’s using force. Could another force lift it? Magnets can.” Use a magnet to catch the clip and lift it up. Then set the dowel under the Duplo towers. Lift the clip up and hold it under the magnet. The trick here is to make sure your string is exactly long enough that you can hold the clip at a place where the magnet will help it levitate… float in the air without touching the magnet. Explain that magnetic force is holding it up, because when we move the magnet close enough to the clip, its pull is stronger than the pull of gravity.

Optional Group Activities: We poured some items on the floor, then had kids collect them with magnet wands, then sorted and counted what they’d collected.

Then we played with the DIY marble run pieces on the slide. IMG_20151212_160029689

(One of the kids had discovered that they could stick magnets to the slide, which would have never occurred to us!) This was fun for the little ones and the parents who were there, because the kids could climb up the slide and drop marbles down, and the parents could tinker and keep re-adjusting the pipes so the kids would be successful in getting a marble all the way from the top of the maze to the bottom.

We played a magnet game in which we would “switch their poles”. If the teacher said “south pole” they were all attracted toward her and would run toward her, if she said “north pole” they were repelled and moved away. It’s basically red light, green light with a twist….

Follow-Ups: For “homework” – here are some things parents could do with their kids to reinforce the ideas learned in class.

  • Have the child go around the house with a magnet or magnet wand. What does it stick to? What doesn’t it stick to? Why?
  • Sorting games: miscellaneous small items in a dish (or bury in a sensory material like rice or beans). Use a magnet wand to sort into magnetic and non-magnetic.
  • Use magnet wands and jingle bells to make jingle wands.

Resource

Community Resources for Science has a nice lesson plan on magnets, which includes tie-ins to the Next Generation Science Standards for third graders.

Magnets first appear in the Next Generation Science Standards in third grade:

3-PS2-3. Ask questions to determine cause and effect relationships of electric or magnetic interactions between two objects not in contact with each other. [… examples of a magnetic force could include the force between two permanent magnets, the force between an electromagnet and steel paperclips, and the force exerted by one magnet versus the force exerted by two magnets. …. how the orientation of magnets affects the direction of the magnetic force.]
3-PS2-4. Define a simple design problem that can be solved by applying scientific ideas about magnets. [… examples include constructing a latch to keep a door shut and creating a device to keep two moving objects from touching each other.]

In my mind, the key ideas I hope my 5 – 7 year old students will leave class with are: Magnetism is an invisible force. We can’t see it, but we can see how it affects other things. Magnets attract ferrous materials (materials containing iron.) Magnets have two poles (north-seeking pole and south); opposite poles attract, same poles repel (push away). A magnetic field can reach beyond a magnet, so a magnet can affect things that are nearby but not touching the magnet.

Safety notes:

Magnets can be hazardous if swallowed. If a child has swallowed multiple magnets, they may need surgery to prevent internal damage. If you are working with young children who might put things in their mouths, use only large magnets, like magnet wands – nothing that could possibly be swallowed.

Very strong magnets can snap together suddenly and pinch skin between them, which is quite painful.

Force – Science for Kindergarten

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Amongst the Next Generation Science Standards for kindergarten is K-PS2 Motion and Stability: Forces and Interactions. Here is the text for that standard:

K-PS2-1: Plan and conduct an investigation to compare the effects of different strengths or different directions of pushes and pulls on the motion of an object. 

K-PS2-2: Analyze data to determine if a design solution works as intended to change the speed or direction of an object with a push or a pull.

These are the Disciplinary Core Ideas:

  • Pushes and pulls can have different strengths and directions.
  • Pushing or pulling on an object can change the speed or direction of its motion and can start or stop it.
  • When objects touch or collide, they push on one another and can change motion.
  • A bigger push or pull makes things speed up or slow down more quickly.

Every kindergartener already knows all these things. Especially kindergarteners who have been given lots of free play time exploring objects hands-on. They know that they can either push or pull their friends on a wagon. They know that the faster they pull, the faster the wagon goes. They know that when they crash one toy car into another, it shoves the car out of the way. They know that if they want to swing really high, their parent needs to give lots of big strong pushes. They know that they can try to slow down their dog by pulling back on the leash. They know they can close a door gently or push it hard and fast so it slams closed. They know that how well something moves after a push depends on its size, shape, and weight. They have plenty of hands-on experience with these ideas. When we “teach” these ideas, we’re just helping give them vocabulary, and helping them to notice and define what they already know.

The way I structure a science lesson is to first have “discovery time”. I put out multiple activities that allow them to experience the science first. Then I do the formal teaching of the concept and vocabulary. Then, I offer “tinkering time” where they get to explore the idea again, reinforcing the theory they’ve just been taught with the concrete hands-on experience that helps them to understand it and remember it.

We have taught Force as part of our Simple Machines unit, and we have also taught it in conjunction with Gravity and Magnets. Here are a collection of ideas for teaching Force.

For K-PS2-1: compare the effects of different strengths or different directions of pushes and pulls on the motion of an object

  • Attach a string / rope to items and let children pull them around a room. Even better, give them a rope to try tying on to things and seeing what all they can pull.
  • Put out items kids can push – the bigger the better – small kids love moving big things.
  • Sit in a circle. Have one child push a ball to another child. They stop it, then push it to someone else.
  • Play soccer or any other ball game that’s about “pushing” the ball to each other, stopping it, and pushing it back.
  • Put out items kids can crash into each other. For example, set up a ramp and toy cars for a demolition derby, where cars rush down the ramp and crash into whatever is at the bottom of the ramp
  • Tell kids to move around the room and find things that they can push or pull (could be almost any object, but can also be a door, a window shade, zipper, socks, etc.)
  • On the playground: encourage the children to experiment with pushes. On the swings, do they move faster by themselves, or with a few light pushes or with some strong pushes? On the merry-go-round, do they move faster if they push themselves, if one person pushes, or if three kids push? (Option: you can time how long it takes to make a full rotation with each method – see details here.)
  • Play tug of war. First have one side pull while others do not – what happens? Then have both sides pull gently, then both sides pull hard, and so on.
  • Play tether ball, pushing the ball back and forth.
  • Use pipettes or eye droppers to pull liquid in, then push it out.
  • Bowling: set up pins and give them a ball to knock them over. (You don’t need an official bowling pin set – toilet paper roll bowling works just fine.) For a fun bowling variation, try pendulum bowling. Or create a wrecking ball to knock over towers.
  • Scooters: if you have those little Scooter Boards, then have kids pull each other around the room, then push each other, then have two kids sit on scooters right next to each other and push each other. See it: www.youtube.com/watch?v=0ZuYUCdWT_s.
  • You could also have kids bring their wheeled ride-upons from home: bikes, trikes, scooters, etc. They move their friends around. Friends need to describe whether they are being pulled or pushed.
  • Have pushing races. Have four types of objects and a track with distances marked (could just be a flattened cardboard box with distances marked on it. They can test each of the objects: if they push gently, how far does it travel? What if they push hard? Which object travels the farthest?
  • Offer a worksheet where children can describe whether the illustration shows someone pushing or pulling.

Note: although this standard explicitly says that “assessment does not include non-contact pushes or pulls such as those produced by magnets”, when we teach Force in our magnets class, we do demonstrate and play with these non-contact pushes and pulls. Children as young as 3 are easily able to grasp the idea of pushing and pulling with magnets.

For K-PS2-2: Analyze data to determine if a design solution works as intended to change the speed or direction of an object with a push or a pull.

  • Use a marble maze toy or a ball wall where kids line up pipes and tracks just right to give the ball a path through the maze.
  • Use a cardboard box lid, craft sticks and a glue gun to make marble mazes where kids tilt the box lid back and forth. As gravity pushes the ball, the sticks change its direction of motion.
  • Set up a ramp to roll balls down. At the bottom of the ramp, place various objects – see if the stop or re-direct the ball’s motion when it hit. Directions here.
  • Set up domino chains and knock them down or create other Rube Goldbergs.
  • Use catapults – push on one end to launch items in the air.

Note: although the standard says “assessment does not include friction as a mechanism for change in speed”, we do end up discussing friction during our Simple Machines unit. We cover it when talking about Wheels and Axles. Our 3-4 years olds experience friction but can’t articulate an understanding of it, but our 5 year olds certainly can.

If you’re teaching force as part of a simple machines unit, you want to convey that all simple machines transfer force. They may change the direction and/or the strength of the force. Most simple machines make things easier by allowing you to use less force to do the same amount of work.

Optional Extensions

Michigan’s Grade Level Content Expectations add:

  • describe the position of an object in relation to other objects (above, below, etc.)
  • describe the direction of movement (away, toward)
  • when the motion of an object is changed by a force, the amount of change is related to the mass of the object; when an object does not move in response to a force, it’s because another force is being applied to it

There’s a lot you could do with learning the vocabulary of positions and direction of movement: play games where you ask kids to go behind, above, into, and so on; read books and ask them to describe the positions in the pictures; play Simon Says – “run away from the wall,” “run toward the swings”, “run around the tree.” Give each child a toy, and have them place it in front of them, then behind them, above, etc. Shake the shaker above your head, behind your back, and so on.

Challenge kids to push a wide variety of objects, including some they will not be able to push – a desk that is too heavy for them to move, or a tree that is rooted to the ground. Ask them to make observations about why it won’t move.

Circle Time – Explaining the Theory

I love starting with this idea from Mrs. Meyer’s Kindergarten: Brainstorm all the different ways kids can move: jump, roll, run, fall, etc. Then put out a bucket of items and ask the kids: can those things move by themselves? Kids quickly say that no, those things need help to move. Ask how they would move them: push, pull, throw, drop, etc. Tell them that when we push or pull on something to move it, we are using “force.”

Set a block on the ground in front of you: ask – “can I move it with my mind?” (they all shout no). “Can I move it by just telling it to move?” (No) “How do I move it?” (Use your hand.) Set your hand on it, but don’t push. “How come it’s not moving?” (You have to push it!) “Now it’s too far away from me – how do I get it back?” (Pull it!) Now I want to push it to [name a child]. How do I do that?” (Push it!) Push it gently. “It didn’t go far enough. What do I do?” (Push it harder.) Push it to the child, and have them push it back.

Then ask them “What if it’s really icky, and I want to move it, but I don’t want to touch it?” Talk them through helping you find a stick to push it with, or another solution.

Ask what the difference is between push and pull – push moves an object away from you (where the force is being exerted) and pull brings it toward you.

Sing a song, or read a book.

Song

Here’s a really simple song: www.youtube.com/watch?v=XZlqas0tixo and here’s a video which shows it in action, with hand gestures, in a classroom setting: www.youtube.com/watch?v=hhXuDlJfKWU

Try this Push and Pull song to the tune of Row Your Boat… it starts Push, push, push your cart, gently through the store. Fill it full with lots of things, then let’s add some more.

There’s also this song: www.youtube.com/watch?v=FOcY37oGhj8

Books

And Everyone Shouted, “Pull!” by Claire Llewellyn. Described as a ‘first look at forces and motion’, this is a great read-aloud for ages 3 to 5. It engages them in the story of animals trying to get items to market, and loading up and pulling the wagon.

Give It a Push! Give It a Pull!: A Look at Forces by Boothroyd. For ages 4 – 6. The text is quite good – the graphic design a little cluttery. The big picture ideas it addresses are: A force is a push or a pull. Sometimes the cause of a force is invisible [wind, gravity, magnets]. Forces put things in motion. Stronger forces can make things move farther or faster. Friction is a force that slows things down. Force can change the shape of things.

We have also used Forces Make Things Move by Bradley and Move It!: Motion, Forces and You by Stille.

Here are other books that are recommended for teaching force:

  • Motion, by Darlene R. Stille
  • How Things Move, by Don L. Curry
  • Push and Pull, by Lola M. Schaefer
  • Push and Pull, by Patricia Murphy
  • Push and Pull, by Charlotte Guillain
  • Move it!: Motion, Forces and You, by Adrienne Mason

Resources

There is a great full curriculum on forces and motion for kindergarteners at http://www.mccracken.kyschools.us/Downloads/PUSHES%20and%20PULLS%20-K.pdf

And another nice lesson plan here: https://spweb.tbaisd.k12.mi.us/sites/home/instructionalresources/science/pk8resources/Kindergarten/Kindergarten%20Unit%202%20Pushes%20%20Pulls.pdf

If you’re teaching older kids about force, inertia, Newton’s laws of motion, there’s lots of great activity ideas in this lesson plan from Lakeshore.

Rainbow Spectroscope Kit

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In last year’s Rainbows class, we made our own spectroscopes from paper towel tubes, tape, and CD’s. (Learn how here.) The original idea was from Buggy and Buddy. They were a pretty easy project, with pretty good results. Using cardboard tubes from the recycle bin fits in with our style, but scaring up 30 used CD’s each time we do the project can be a pain. (Yes, I know I could buy blank CD’s, but that somehow feels like it’s violating the goal of trying to use recycled items when possible.)

This year, we discovered the Rainbow-Scope Science Kit on Amazon. (You can also order direct from Nature Watch.) They run about $1.75 per scope, once you count for shipping. It looked like they would produce a nice looking result, with maybe more consistent spectroscopic images than the DIY ones. We decided to give them a try.

Here’s what comes in the package: cardboard tubes (the size of toilet paper tubes, but much sturdier, purple foam disks for one end, with slits cut in them, red foam “donut” shape disks for the other end, diffraction lenses, glue, tube wrappers to decorate, a prism, instructions, and handouts with additional scientific background on spectroscopes and light, and ideas for extension activities.

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To assemble:scope

1. Put a little glue around the inner rim of the red foam circle, then set a diffraction lens on it, centered over the hole. (Important to emphasize to the child to use as little glue as possible. If there’s too much, it oozes onto the lens and blocks your view.)

2. Have the child decorate the wrapper, coloring in each band with the appropriate color marker.

3. The child smears glue stick all over the tube, then you help align and glue on the wrapper.img_20170109_195729318

4. Glue the purple foam circle on one end. (Near the “violet” band on the wrapper.)

5. Hold the tube up so you can look through it up at the light. Hold the red circle on the open end (the one you’re looking through.) Rotate the red circle till you see horizontal bands of color next to the light. Then glue it on.

The materials were good quality. It produces a nice result for a “take home project.” (See photo at top.) Our three to four year olds were able to decorate their wrappers themselves, but needed an adult to do all the assembly. Our six and seven year olds could do most of it, but you really need an adult for step 5.

Here’s what you see when you look through the spectroscope (click on any image for a larger view)

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These are, from left to right: light reflected off a desk, computer screen, moving toward a ceiling light, hanging kitchen light, Christmas lights, and ceiling light.

Overall, this is a good project for our class.

Light and Shadow Experiments for Kids

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This week, we got to play with light and shadows!

Book / Big Picture light-and-shadow-book

I wrote a book for this week’s class, which covers all the key ideas about light and shadow. It includes lots of easy experiments to try. You can read it (or print a copy) here.

As always, the class structure was that we began with “discovery time”, where the kids had an opportunity to explore all the activities hands-on, and start discovering how things work, testing theories, having questions arise, and making observations. Then we had opening circle, where we read the book, which explains the phenomena they’d observed. We also did several of the demos included in the book during circle, and then encouraged them to try out all those same experiments during our “tinkering time” where they return to exploring all the activities, this time with a theoretical framework for what they’re seeing.

Note: the book is a bit long and packed with a lot of ideas for one circle time for this age group, so in our afternoon class, we read pages 1 – 10 and 21 – 22 during opening circle. We saved pages 11 – 18 about daytime and night-time shadows, and pages 19 and 20 which introduce the terms opaque, translucent, and transparent for closing circle.

Activities

Shadow-making Screen. My co-teacher built a fabulous screen of a white sheet supported by a PVC frame. It was held up by two very heavy umbrella stands so even with a fair amount of rough-housing, it never came close to tipping over. (If you don’t have umbrella stands, you might be able to build PVC legs and duct tape them to the ground?)

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Behind the screen, we had an LED Work Light, which was very bright, but cool to the touch. (PLEASE don’t use an incandescent bulb or halogen shop light as they can get very hot!!) We happen to have an interior room with no windows, so it was easy to get the room dark enough to get good shadow effects – it might be harder in a window-filled room.

Shadow Play: Experiment with shadow-making screen. This was a free play station.  We had posters showing diagrams of hand positions for shadow puppets to inspire them to play with hand shadows. I made a poster showing how to do the 7 shadow puppets that appear in the book Shadow Night which we would read in closing circle. (see below)

We had stuffed animals and shadow puppets that they could use to make shadows.

They could also make their own shadow puppets to test, or bring in other items from the classroom to see what shadows they would cast. (For example, in the photo of the shadow of the stuffed horse, you’ll notice some rainbow colors – those were the result of putting rainbow colored transparent “Legos” in front of the light source. In the 5th picture, you’ll see a Duplo sculpture a Dad made.)

Or they could just do crazy dances behind the screen! (Often kids on the “audience” side of the screen would mimic the motions of the child behind the screen.)

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Art Project – Shadow Puppets. We had cardstock, markers, scissors, tape, and popsicle sticks so they could make their own shadow puppets. The first year, we made the mistake of putting out white paper and no examples, and there were some puppets that were lovely stick puppets (see the top picture below). But all those marker decorations on the dragon will never show up in a shadow. What we needed to communicate better was that the point of a shadow puppet is the outline / silhouette.

This year we had some sample puppets, and we put up a poster with more sample puppets to give kids a better sense of what kinds of designs to make. (We had parents who did some great TMNTurtles and a great Darth Vader mask I didn’t get a picture of.)

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Flashlight Play: In the center room, we also had lots of flashlights, mirrors and toys, so kids could freely play with reflecting light, and with playing with how they can change the size and shape of a toy’s shadow depending on how close or far away they hold the flashlight, and what angle they hold the flashlight at related to the toy. (This was a direct echo of some experiments from our book.)

Laser Maze. We own a great board game called Laser Maze Junior. It’s a Think Fun game, where there are a series of puzzles of increasing difficulty. The child sets up the board as shown on the card, then turns on a laser, sees where it’s shining, and adds mirrors and obstacles to the board to re-direct the light into the goal for the puzzle. Teaches not only the idea of reflecting light, but also a good logic puzzle. Our little kids just dinked around with the pieces, but kids age 5 and up became totally absorbed in working their way through the puzzles.

Reflection – Mirror Boxes. We also built simple mirror boxes (taping together three square mirrors in a half-a-cube shape, and gave kids materials to arrange in there to make symmetrical patterns. Learn more about mirror boxes at Imagination Tree.

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Challenge of the Week – Engineering Project: Sundial. Create a sundial with a paper plate, straw or pencil, tape, glue and glass globules.

If you’re with your kids / students all day on a sunny day, here’s the process: Poke a hole in the center of the plate. Tape a pencil or straw upright in the hole. On an hour mark (at 9:00 exactly or 10:00 or whatever), take the plate outside, and tape it in place in the sun. Mark a line where the shadow falls, and write the time. An hour later, come check the shadow and mark a line for the time again. Repeat on the hour all day long till your sundial is complete. The next day, check it again to show that it’s still working. You can pick up and move the sundial as long as every time you set it down, you orient it the same way. (More info on this project at: www.nwf.org/Kids/Family-Fun/crafts/sundial.aspx or www.kidsplaybox.com/kids-crafts-homemade-sun-dial/)

Since we only have our students for a couple hours, and since the weather forecast was gray skies and rain, my co-teacher prepped a template a few days ahead of time (on a beautiful sunny day) and we did a slightly different process. We put the pencil in the center of a plate, then slid on the paper template, which was smaller in diameter than the plates, then the child could mark off all the times. Then we removed the templates and they decorated their sundials. Then we used a flashlight to illustrate how as the sun moved through the sky, the shadow would shift to indicate the time of day.

As you can see from the third photo, sometimes we put out the supplies for one project (a sundial) and children do something completely different than we had expected… we’re OK with that. We still showed this child how the shadow would shift as the day went on, landing on different Shopkin drawings at 8 am than it did at 1 pm.

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Optional Outside Activity, if the sun is shining: Students set-up their sundials in the sunshine and see where the shadow falls – and check whether it’s correct about the time.

Art Project: Paint Shadows 
(Source for idea: http://tippytoecrafts.blogspot.com/2012/02/negative-art.html)

Basic idea: A child lays their hand on a piece of paper, with fingers spread wide, and you spray paint on to it. (Tell them this is like sunshine shining on their hand – the light rays will spread outward and continue till they run into something that blocks them, and that makes a shadow.) When they lift their hands off, a shadow is left behind. Here’s a poster to explain the idea… the poster also include photos of several ancient cave paintings of paint shadow hands, including some from Indonesia believed to be 40,000 years old.

Logistics: We filled a spray bottle with white kid-safe / easy clean-up paint mixed with water… the goal was to thin it enough that it would spray easily, but not so thin that it would run. The first year, we tried it on the easel, using black cardstock for one handprint per paper take-home project. We had planned for the kids to do the spraying themselves (good fine motor practice) but with our sprayer, if you were too close to the paper (i.e. kid’s arm-length away), the paint stream was too focused. You had to stand back a few feet to get a nice spread-out spray of paint – and no kid could stand that far back and not make a big mess!

This year, we put brown paper on a table, and did a collaborative cave painting, where kids put their hands on the paper and an adult sprayed. It’s very important to have a tub of soapy water and a towel right next to this project so they can wash their hands right away.

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Both years, we’ve really struggled with the spray bottle getting all clogged up with paint and not spraying well. Next year, we may try a different spray bottle, or a different paint, or maybe we’ll get some Body Spray paint.

Sculptural-Engineering Activity:  Kids sculpted a shape or cut a shape from aluminum foil, then taped it to a cardstock square. Then they placed it in front of a bright lamp and traced the shadow then colored in the shadow. (Source of idea: http://doodles-and-noodles.blogspot.com/2012/10/figurative-sculpture.html)

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This activity is best for 6 – 7 year olds. The younger ones had a harder time figuring out how to make a three dimensional sculpture. If you’re working only with little ones, you might find it better to just use plastic toys / action figures and have them trace and color in their shadows on paper. I prefer the sculpture activity where they go home with BOTH the shadow tracing AND the sculpture it’s based on, but for little ones, it was just too tricky.  If you use toys, be sure to choose ones that make fun shadows!

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STEAM Activity: Exploring Light Refraction: Fill several different sizes and shapes of glass jars with water and seal. Put them out with paper and marker pens. Have kids draw arrows or other pictures and look at them through the water filled jars to see how the images change. Some jars will distort images, some will flip them – some have very little effect. Have kids experiment with the different size jars, with different size drawings and moving the image closer or further away. (Idea: http://gosciencegirls.com/refraction-light-glass-water-play-steam-kids/)  Here’s a poster to go with this activity.

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Building Activity: We had translucent “Duplos.” The kids built towers with them, then shone a flashlight to see the colorful shadows. Key to the success of this activity was to just leave the flashlight on, shining through whatever tower was currently there… as kids looked over and noticed that colorful shadow, it intrigued them enough to come and explore. If the flashlight wasn’t on, they were more likely to pass the table by as a familiar “it’s just Duplos” activity.

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Projector Shadows: We have an overhead projector, so set it out with some opaque items (blocks, etc.) and some glass tile samples that make really cool shadows. Here’s a picture of the items on the projector surface and then their image on the wall.

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Light Table and Water Table: Last year, we had the light table out with a variety of translucent items for free exploration. We had the water table filled with colorful water beads floating in water, and a couple flashlights to shine on them, to shine up through the bottom of the table, etc. This year, we put the light table under the water table to shine up through there. and put all the translucent items in the water.

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Optional Indoor Activity #1: Mural of kids’ shadows. You could tape a big piece of paper on the wall. Then shine a big light or projector at it. Have kids stand by the wall so their shadows fall on the paper. Trace their shadows.

Optional Indoor #2: Silhouettes. Put paper on wall. Have the child sit sideways in front of the table. Shine a bright light on them and trace their silhouette.

Optional Indoor #3: Hanging shadows. You could hang a clothesline across a room and hang a lot of items on it. Hand the child a flashlight and turn off the lights – they can walk up and down the line, shining the flashlight at all angles, finding the shadow in the room.

Optional Outdoor Activity: Sunprints. You can purchase special photo-sensitive paper (called sun prints, or sun art paper.) You set it outside in the sunshine, with various items on it for a period of 15 minutes to a few hours (depending on the product and how bright the sun is), then you remove the items. and you’ve capture the image / shadow permanently. (See example here.)  They’re really VERY cool – I love them. BUT… in the Pacific Northwest, I find that they don’t tend to work most of the year – our winter sunlight just isn’t intense enough. I have gotten them to work on hot sunny summer days.

Opening Circle – the no-book option:

This is how we did it last year, before I wrote the book we used this year.

We asked the kids what makes light – what light sources could they think of. As they suggested them, we drew them up on the board to reinforce what was said.

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We demonstrated a few light sources, including a flashlight that created a very diffuse light and a laser pointer which created a very focused light.

We then talked about shadows and when they see them, and what makes them, and so on. We demo’ed some hand shadow puppets on the screen. We did a little mini puppet show with some paper shadow puppets.

We talked about the difference between Opaque Shadows = No light getting through and Translucent shadows = Some light shining through, and demo’ed this with some colorful scarves and the translucent Duplos.

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Song – We’re still looking for a great sing-along about light or shadows for circle. A couple options, both to the tune of Frere Jacques:  (Source 1; Source 2)

See my shadow, see my shadow
Move this way, move that way.
See it do what I do, see it do what I do,
It follows me, it follows me.

I see shadows,  I see shadows,
On the wall,  On the wall.
Some are short and scary,
Some are short and scary,
Some are tall, Some are tall.

Closing Circle

We read the book Shadow Night (see below) and acted out the puppet show with hand puppets at the shadow screen. One of my favorite circle times of the year!

Books (contains affiliate links)

Stories about Shadows

  • Shadow Night by Chorao. A boy sees shadows on his wall and is afraid that they are monsters. He yells for his parents, who come to reassure him, and end up showing him how to make shadow puppets with their hands, and then they tell a story with shadow puppets. The great part is that the book is also a tutorial in how to make those hand shadows yourself!! So, one teacher read the book where the kids could see it, and the other made the shadows on the screen for everyone to see. The book ends with the boy making shadows on the wall, including a shadow monster. Ages 3 – 7. Although it’s long for a read-aloud, it works, when used in conjunction with the shadow screen.

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  • Moonbear’s Shadow by Asch. When Bear is fishing, his shadow scares away the fish. So, he tries to run away from his shadow and tries to trap his shadow, but with no success. At noontime his shadow disappears so he takes a nap, but in the late afternoon, it’s back! But when he goes fishing, his shadow no longer falls over the water. So, he catches a fish – and so does his shadow! A cute story for ages 3 – 5 that also discusses how shadows change as the sun moves through the daytime sky.
  • The Dark, Dark Night by Butler and Chapman. Frog is headed home to his pond after dark and borrows a lantern. When he gets to the pond, he sees a huge black Pond Monster! (The kids in our class were delighted that they all knew this was Frog’s shadow, even though Frog didn’t know that.) He goes and gets friend after friend. They see bigger and scarier Pond Monsters and get more and more worked up. Then at the end, they realize that it’s just their shadows and laugh and laugh. A nice story about shadows and also about how sometimes a misunderstanding can lead to fear and then when we learn more it becomes less scary. Fun for ages 3 – 6.
  • Lights Out by Medearis and Tadgell. Part of the Just for You series featuring African American families. Nice illustrations, good rhythm and rhyme to the text. “‘Good night, sleep tight!’ Daddy tucks me in. Out go the lights. Now the fun begins!” Sweet story of a daddy tucking a child in to bed, then her sneaking out to look at the city lights and make hand shadow puppets and then sneak back into bed. Nice preschool read-aloud or easy read for a new reader.
  • Nothing Sticks Like a Shadow by Tompert and Munsinger. Age 5 – 7 – a much longer book than I would read at story-time, but might work well one on one at home or as a naptime read at a preschool. Fun, silly story about a rabbit who tries lots of ways to escape his shadow – leaping away, sweeping it away, pulling it off, cutting it off….
  • My Shadow by Stevenson. This is a poem from the late 1800’s by Robert Louis Stevenson, and many illustrated versions exist. Some of the words are dated: “he stays so close beside me, he’s a coward you can see. I’d think shame to stick to nursie as that shadow sticks to me!” but overall, still appealing to modern preschool-aged children if the illustrations appeal.

Non-Fiction Books on Light and Shadow

  • Oscar and the Moth: A Book About Light and Dark by Waring. This book is a conversation between a cat and a moth that explains how the earth rotates and that causes day and night, explains that light can come from the sun, the stars, electric light, and animals that emit light. It also explains that shadows happen when something blocks the light. A nice overview of lots of scientific ideas, told in a way that not only makes sense to preschool age children, but is engaging as well.
  • Follow It!: Learn About Shadows by Hall. Non-fiction, covers all the basic ideas about shadows. Does a great job of gathering the key ideas about shadows, but the writing isn’t very engaging. Good resource for ages 4 – 6.
  • Guess Whose Shadow? by Swinburne. Pros – the book includes a basic introduction to the idea of shadows, with photos to illustrate the text, then it has a guessing game, where you see the shadow on one page and it asks you to guess whose shadow it is, then reveals the answer on the next page. The kids in our class (age 3 – 7) were definitely engaged in the guessing game during circle. Cons: the photos are a little dated, and not that great, and there’s just a grammatical incorrectness to showing a picture of a shadow of a swing-set and saying “guess whose shadow.” It’s almost tempting to write / photograph our own version of this guessing game.
  • Shadows and Reflections by Hoban. Like all Tana Hoban books, this is a wordless collection of photographs on a theme. Like all Tana Hoban books, I think this one is fine, and I get it to put on the bookshelf for kids to look at it, but I can’t say I love it.
  • What Makes a Shadow? by Bulla and Otani. A really nice non-fiction overview of everything having to do with shadows. Great for 5 – 7 year olds, or to read one-on-one to a younger child, but too long for a group time with preschoolers.
  • Day Light, Night Light: Where Light Comes From by Branley and Schuett. Branley worked at the Hayden planetarium and has written many kids’ science books. Like his other books, this is a really good summary of the scientific facts, for kids 5 – 8. We don’t read his books in class because they’re too long and over the heads of half our kids, but they’re quite good.
  • Science Chapters: All About Light by Halpern. The description says it’s for ages 6 – 9. I think it’s most appropriate for the older edge of that – it’s over the head of the kids in our class (age 3 – 7.)
  • More ideas for demos and activities here: https://stardate.org/sites/default/files/pdfs/teachers/ShadowPlay.pdf

Videos and Apps

Optional Arts Extension – Shadow Puppet Theatre

 

Electricity – STEM for Kids

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Here are the activities we used to explore electricity in our Family Inventor’s Lab, a STEM class for families with kids age 3 – 7.

Experiments with Electrical Circuits

Lighting a Bulb: The simplest, most straight-forward way to illustrate a circuit is to use a lightbulb on wires, and hook it up to a battery. You hold up the lightbulb and ask why it’s not lit. They say because it has no power. You hook one wire to the battery, then ask them if it’s lit. Then hook the other wire up. Now the light comes on. Point out the circuit – the electricity is pushed by the battery into this wire, then through the light, then through this wire back to the battery.

We used a 6 Volt Lantern Battery and some old lightbulbs on wires we have in the store room. (I can’t find ones quite like this on Amazon or at Radio Shack now, but you could do a similar experiment with LED bulbs and a less powerful battery.)

You can also add in a switch so they can see how the switch interrupts the circuit. We had mechanical switches and DIY switches we could include in the circuit. (If you don’t already own these materials, there are several simple kits that include the basics, such as School Specialty 560962 or the Eisco Labs kit.)

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Challenge: Can you create an electric circuit using play-dough?
We made two batches of play-dough, one conductive (made with salt and cream of tartar) and one insulating (made with sugar and distilled water). See recipes at http://courseweb.stthomas.edu/apthomas/SquishyCircuits/ or www.instructables.com/id/How-to-make-conductive-play-dough/?ALLSTEPS.) We also had battery packs and LED Lights.
A simple circuit involves taking two balls of conductive dough. Push one wire from the battery pack into ball 1 and the other wire into ball 2, then insert one wire from the light into ball 1 and one into ball 2. Show the children the circuit.
Then play with it from there. What happens if we push the two balls together? We create a short circuit. The electricity just passes through the play-dough, not lighting the light. What if we put a layer of insulating dough between the two balls – light comes back on. Have the children test several lights, and sort them by color. (Note – they shouldn’t touch the wires on the lights directly to the battery terminals – that can cause them to burn out.) Have them build series circuits. There’s a lot more you can do with “squishy circuits” made of play-dough. Here’s a video of a TED talk on why squishy circuits are cool for kids. http://courseweb.stthomas.edu/apthomas/SquishyCircuits/

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Lemon Battery Battery: So, on many websites, and in many kids’ books about electricity, you’ll find directions for a lemon battery – you put a penny and a zinc screw in a lemon, and use it to light a lightbulb.

The science behind this is something like this: What’s happening in a voltaic battery: two electrodes – one copper and one zinc – are submerged in an electrolyte – an acidic solution (lemon juice in this case). Zinc and lemon produce electrons and copper and lemon lose electrons. Electrons pass through the lemon juice from one battery terminal to the other, creating electricity.

The idea for the experiment is: roll the lemon with some pressure to get it juicy, then insert into the lemon one zinc item (screw or eyelet) and one copper item (copper wire, rivet or copper penny – from before 1982 when pennies were more copper than zinc). Be sure the two metals don’t touch. Then take a lightbulb on wires – touch one wire to the zinc item and one to the copper to light the bulb. (Or so several sites / books claim.) We found that the current produced by the battery was way too weak to light even a very low voltage LED. We did get a voltmeter which could measure the current to show a small reaction was happening.
Apple Battery: This year, we used a Granny Smith apple and copper rivets. You take a wire from the battery pack, wrap it around a rivet, and push it into apple #1. You take the other wire, wrap it around a rivet, and push it into apple #2. Then take the probes for the voltmeter and place them in the apple – be sure to put the red probe into the apple with the red wire, and the black probe with the black wire. The voltmeter will register the electrical current. Our older kids understood that the voltmeter indicated electricity was passing. Our younger kids didn’t get that, but they liked pushing the rivets into the apple. 🙂
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Playing with Electrical Tools / Toys

Create electricity with a hand generator: We had a crank-powered flashlight and emergency radio plus several small flashlights with dynamos. (Like these, but we got ours in the Daiso dollar store for $1.50 each.) These were a great free play activity for the active kids – we turned off most of the lights in one room and they just played with flashlights and did flashlight tag.

Plasma ball: We had one of these to let kids see the “lightning”: Sphere Lightning Lamp

littleBits: We had the littleBits Electronics Base Kit. littleBits is kind of the Lego of electrical circuits. It’s a modular system, with little bits that click together with magnets, so it’s easy for even small children to assemble them correctly. There are inputs (buttons, dimmer switch / volume control, sound activated switch, etc.), and outputs (lights, buzzers, motors, etc.) The base kit comes with an instruction book to explain the basics, but also “ideas to get you started” on other things you can invent. I have a detailed review of littleBits and Snap Circuits here.

Here is a basic configuration: power cell, input switch (a push button) and an output (a bright LED light.)

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Snap Circuits is another modular electronics kit. Kids snap items on to the base plate, such as battery packs, switches, lights, and motors. Then they snap on wire modules to complete the circuit. The set comes with an instruction manual, but I’ve created my own simplified directions for 5 of the projects. Our 5 – 7 year olds could assemble them but they were beyond the fine motor skills/strength and beyond the cognitive grasp of our little ones. Find a detailed comparison of these and littleBits here.

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Sensor Toys: Ok, I know you’ve all seen toys during your life where if you touch two metal contacts on the bottom, it completes a circuit and the toy does something.

Years ago, my daughter got a toy chick one Easter that would chirp when you held it in your hands. When she brought her chick to kindergarten, she and her classmates discovered all sorts of cool concepts about electricity by playing with it. For example, if one person touches one contact and another person touches the other contact, the bird does not chirp. But then when those two people hold hands (to complete a circuit) the bird chirps. The bird chirps when set on a metal surface but not if set on wood or rubber, and so on. Her teacher, a master of emergent learning, was so excited by this. He said he wanted to jump in with “ooh! ooh! it’s electricity” and explain it all at the start of the day. Instead, he told me he “sat on his hands” all day and didn’t explain it until the end of the day when he asked the kids to share all the things they learned, make observations about what made the chick chirp and what didn’t, and what they thought was the reason. And only after that discussion did he explain the principles of electricity.

For our class, I found a battered Easter chick at Goodwill, and I ordered this Tedco Sensor Ball which flashes and makes noise. (This Energy Stick looks like a great option, plus if you look at that item on Amazon, it suggests several other related products.)

Operation. We put out the classic board game Operation. The goal of the game is to use wire tweezers to pick little pieces of plastic out of openings without making it buzz and light up. So, let’s look at the science… why does it light up and buzz?

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Our 3 – 4 year olds basically just had fun setting off the buzzer over and over. Our older kids got both the point of the game (to try to get the plastic out without hitting the buzzer – a great fine motor challenge) AND got the idea of the electrical circuit. Here’s a poster to go with this activity.

Static Electricity

Weather Note: There’s lots of great static electricity activities you can do, but it’s worth noting that your success will depend a lot on the weather! We figured that in January, our classroom air would be quite dry due to all the forced air heat that was blowing through the room. However, when the outdoor humidity is at 85% as it was last Saturday, your static electricity demonstrations will be less effective than you had hoped…

History and an Experiment to Go With It: 2,500 years ago a Greek mathematician and astronomer named Thales (TAY-less) first noticed the effects of static electricity. He was polishing a piece of amber, with a piece of wool or fur. Thales discovered that after he rubbed the amber that it attracted dust particles or other light objects like straw or feathers. (More history here: http://inventionofelectricity.weebly.com/contributors.html)  You could re-create this in class with amber, sheep skin, and feathers.

Static Station. We offered multiple ways to generate static electricity – balloons kids could rub in their hair, combs and a plastic ruler that they could rub plus wool and silk to rub them with. Then we offered multiple items that will react visibly to the pull of static electricity. Some options are: puffed rice cereal, torn up tissue paper, plastic tubes filled with Styrofoam pellets, feathers, rabbit fur, and an empty aluminum can. You can also have a plate of salt and pepper. Wave the static charged balloon over it – the pepper will fly up first, and the heavier salt will be slower to attract. You could have a contest where kids charge their balloons, then stick balloons to a wall, and see whose balloon stays stuck the longest.

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Light a bulb with static: Our teacher rubbed a balloon on her hair to build up a static charge, then held the balloon to one end of a compact fluorescent bulb, and it made it light up briefly. (It worked better in the morning class before the humidity spiked outside!) Learn more at: http://www.csiro.au/en/Education/DIY-science/Physics/Light-up-your-light-bulbs

Make Lightning: http://www.learnplayimagine.com/2013/04/how-to-make-lightning.html has two methods for getting a spark. We haven’t tested these.

Water table: Have a static generator (balloon and hair, or amber and wool, or comb and wool) next to the water table. Charge it up, then pour a trickle of water past it – will the static electricity “bend” the stream of water? Here’s a poster to go with this.

The bending water is a little subtle. The littlest kids don’t really get it. The 5 – 7 year olds would understand it if FIRST we showed that normally when you pour water, it flows straight down, then we showed how the static bends the water.

Alternate water table idea: Put in scoops and water wheels. Put pictures of water wheel generators next to the table so you can explain how, before the invention of electricity, water wheels on streams were used to do work (like grind grain or pump bellows.)

Art: We’ve tried a few ideas, which are tangentially related to electricity.  1) drawings with Spirograph to represent electron orbits. 2) Scratch art pictures of lightning bolts… scribble with oil pastels to fill a piece of paper with bright colors. Paint over that with dark blue/black acrylic paint like the night sky. While the paint is still wet, use a stick to draw lightning bolts – it will move the paint aside to reveal the colors below. 3) Use electricity to draw by using a record player turntable. Put a paper plate on where the record goes, turn it on, and draw. 4) You could build a Scribblebot and use that to make art. You tape three markers onto a plastic cup to form “legs” on the robot. Add a motor and a battery, and your scribble bot dances around, leaving a drawing behind.

Tissue Paper Art: On I Heart Crafty Things, we found this great idea for a butterfly made of tissue paper where the wings will flutter in reaction to a static electricity source such as a charged up balloon. My co-teacher had the seasonally appropriate idea to do a tree instead, where the fall leaves flutter. They cut leaves out of tissue paper and Mylar wrapping paper. The key thing you need to explain to the kids is to only glue down PART of the leaf. They need to leave most of the leaf loose to flutter. Here’s sheet of instructions.

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Circle Time – Static Electricity

There are two big ideas to communicate: 1) things are made of atoms – atoms are made of protons, neutrons, and electrons. 2) Sometimes when things rub together, they lose electrons, and that “charges up” the item with static electricity.

Parachute: Begin by playing with the parachute. Especially do games where the kids are under the parachute that’s going up and down. After a while, point out how all their hair is standing on end. It’s charged with static, and the hairs are “repulsing” each other and trying to move away from each other.

If you want a theme song, play the Schoolhouse Rock Electricity Song. When it says anything else, ripple the parachute, but whenever it says “Electricity, Electricity” raise and lower the parachute twice.

History: Share the history of Thales, mentioned above.

Grounding in their Experience: Ask “have you ever slid down a plastic slide and then gotten a shock when you touched someone? Have you ever played parachute games at circle – did you notice that for the kids who went under the parachute, their hair would then stand up straight? When your parent gets laundry out of the dryer, have you ever seen a sock stuck on to something? That is static electricity.”

What’s happening? Explain that all things are made of atoms. Little itty bitty particles we can’t see. (There are millions in one eyelash.) Each atom is made up of three parts: protons and neutrons are held together tightly in the middle. Electrons are negatively charged and they’re held loosely. [Illustrate this with 3 balls of playdough – stick two together to be the proton and neutron, then use the other ball to show the orbiting electron.] Electrons bounce from atom to atom easily. So, when there’s a static charge in my hair, because I’ve been playing under the parachute, an electron might jump away from me to something else. [Show with the play-dough electron.]

Static electricity demos: Use your hair to charge a balloon, or fabric to charge a comb, then demonstrate how tissue paper reacts, or how you can pick up rice cereal with it. These things are attracted to each other. Then lay an empty aluminum can on its side, and hold the static item near it. The can will either roll toward the balloon or away. (Learn more at Exploratorium.) Light a fluorescent bulb with static electricity.

Circle Time – Electricity

Our third big idea is: For electricity to work, you need a complete circuit. You connect the negative terminal on the battery to the output (a light or a buzzer) with something that conducts electricity (wire, water, conductive play-dough), then connect the output back to the positive terminal. This allows current to flow continuously.

Ask the kids what they know about electricity, and how we use electricity. This grounds the rest of the discussion in their experience.

Song: My co-teacher wrote a simple song, that goes:
Electricity is a powerful thing… I know, I know…  Electricity is a powerful thing… I know, I know…
Then we ask kids to suggest something that they use electricity for, and we substitute in those words.
Electricity lights our streets…  I know, I know. Electricity lights our streets, I know, I know.
Electricity warms our Homes… Electricity starts our cars… Electricity makes lightning >boom<  (Etcetera 🙂

Intro: Thanks to the work of lots of scientists and inventors throughout history, we’ve figured out how to capture and store electricity. One of the places we store it is in a battery. We’ve also figured out how to help move electrons so they do work. For example, they can light a light, make a buzzer buzz, or turn a fan, like we did with the Snap Circuits and littleBits. To make any of these things work, we have to hook up the power source and the thing we want to power so electricity can move from one to the other.

Circuits Demo: Use the batteries and lightbulbs and switches to demonstrate the idea of circuits and how current passes through a circuit. And how a switch interrupts the circuit.

Pass the current: Have kids hold hands in a circle. Squeeze a child’s hand, they squeeze the next hand, and so on, to pass the current all the way around a circle.

After you have done this, use your sensor toy (see above.) You touch one sensor. Have the child next to you touch the other sensor. Nothing happens. Hold hands with that child – you’ve completed the circuit – the light comes on, or the chick cheeps. Now, let go of that neighbor’s hand, and take the hand of the child on your other side. Have all the children join hands, so kids can see that the current travels from you through all of them, back to the sensor. When we all hold hands, the chick cheeps. If anyone lets go, it interrupts the circle, and the chick stops cheeping.

You could also play either of the games described below.

Books:

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Books for Circle

I honestly haven’t found any I love. I’m working on writing my own. 🙂

  • Oscar and the Bird.  When Oscar the kitten finds a tractor in a field and accidentally turns on the windshield wipers, he is full of questions about electricity. Luckily, Bird knows the answers! With the help of his friend, Oscar finds out how electricity is made and stored, which machines need electricity to work — and why we always need to be careful around wires, batteries, plugs, and sockets. Ages 4 – 8. This would be a great SECOND book to read if we’d first read a book with a nice summary of basics of electricity.
  • Electricity: Bulbs, Batteries, and Sparks (Amazing Science). A little long, but otherwise a good circle book for ages 5 and up. (skip the “fun facts” when reading aloud.) Over the head of younger ones.
  • Switch On, Switch Off by Berger. Library description: Explains how electricity is produced and transmitted, how to create electricity using wire and a magnet, how generators supply electricity for cities, and how electricity works in homes. Ages 6 – 8. Probably too long for circle.

Good resource books for older kids (age 5+) and for experiment ideas. Not for circle.

Group Activities

Electrons: Explain that all things are made up of molecules (reminder of the states of matter activities last week.) All molecules are made of atoms. Atoms are made of protons and neutrons which hold tight together in the nucleus, and electrons are held loosely. Give each child a die (or a coin) where some/one side is labelled “proton or neutron” and one is labeled electron. On each turn, they roll their die or flip their coin, then pick it up. If it says proton or neutron, they run to the center of the room and huddle together. If it says electron, they orbit in a circle around the protons and neutrons.

Pass the Electron Game: This idea started with an idea on Hub Pages: http://hubpages.com/education/electricity-lesson-plan  Have all the kids stand in a line. Tell them they are a copper wire. Give each one electron (a ball or other small toy). Tell them they’re a balanced copper atom. But, when the battery (the teacher) gives an extra electron to one child, they have to pass on one of their electrons as quick as they can. When the extra electron gets to the end of the line, flash a flashlight to show the electricity was discharged. We tried this in our morning class – the teacher told them that they should take the new electron in their left hand, pass the old one on, then pass the new one to the right hand. But it turned out that it was too much of a small motor challenge for our three and four year olds – they had a hard time transferring balls from hand to hand. There are two ways to fix that. One is that they hold THEIR electron in their left hand the whole time and always use their right hand to take and pass the new electron. The other is what we did in our afternoon class, where we just pretended they were holding their own balanced electron, and the only moving ball was the extra electron that was passed to them. We were then able to pass several electrons at once, for a “hot potato” style game. You can also curl the end of the circle to complete a circuit.

 

Cartesian Diver Bottles

As part of our study of Sink and Float and Submarines, we re-created a classic experiment: the Cartesian diver bottle. Here’s a video of our final product in action:

The basic idea: You take a large plastic bottle filled with water, then add a “diver” who floats. When you squeeze the bottle, he dives to the bottom. When you release pressure, he returns to the surface.

The science behind it: Why does it work? The diver has an air bubble trapped inside, making the density of the diver a little less than the water, so it floats (it’s positively buoyant). When you squeeze the bottle, it increases the pressure, water is forced up into the diver, and the air bubble trapped in the diver compresses (gets smaller). Water is denser than air, so this increases the mass and density of the diver, so it sinks. When you stop squeezing, the air bubble expands, forcing water out of the diver, and the diver rises. (Sources: Steve Spangler, Science BobPhysics.org.)

The history: In 250 BC, Archimedes described buoyancy

Any object, wholly or partially immersed in a fluid, is buoyed up by a force equal to the weight of the fluid displaced by the object.

In the 16th century, scientist and mathematician Rene Descartes is said to have invented this experiment which demonstrates buoyancy.

Options for the diver

Criteria: You need something that can contain some air or catch an air bubble underneath it. You need to be able to adjust the weight till you get it just right. It needs to fit through the bottle opening. It needs to just barely float.

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Building, Testing and tinkering with the diver: Have a cup full of water to test in. Set the diver in. He should just barely float. If he sinks, remove some weight or add more air. If he tips over onto his side, add more weight to the bottom. Keep adjusting till you’ve got him just right. This is the hard part…

Assembling the bottle: Use a plastic bottle, like a one-liter water bottle. Remove the labels to get a good view of the dive. Fill it almost all the way. (If you fill it all the way, then when you add the diver, he’ll displace some water, and it will spill out.) Gently add the diver. Screw lid on tight. Squeeze to test. (You’ll have to squeeze hard.)

Have fun tinkering!