During our Simple Machines unit, our final unit was on Wheels and Axles.

Challenge Project – Build a Toy Car

Our challenge projects are designed so that parents and children can build them together. Our 6 year olds might be able to build one independently, but our 3 and 4 year olds definitely need help.

We have two different versions we make. This one is powered by a small motor and fan. You can find the tutorial at Build a Car.

This one is powered with a rubber band, so the cost is lower. Watch this instructional video, or click here for the full DIY Car tutorial.

Free play:

We pulled out our whole collection of toy trains and wooden tracks, and let them assemble tracks that trailed all over the room. (You could also put out cars and car tracks.) Some kids (generally boys) will gravitate to this activity and stay there the whole class…)

We’ve got these great wheels that can be attached to any cardboard box. (Sadly, they’re not made any more…) They’re really well built and easy for a small child to use. And any time you’re done with a box creation, you can take off the wheels and save them for the next time. We had one box with wheels, and one box that was the same size without wheels. Kids could load them up and see which one was easier to move.

We also had wooden dowels, and a basket – kids could load up the basket and roll it back and forth on the dowels.

Water table and sensory table: We have water wheels they were able to play with. It would be really cool to build your own water wheels. Here’s ideas on how to do it: http://iijuan12.hubpages.com/hub/wheels-and-axles-lesson-plan-in-simple-machines-unit

Building

LOTS of building toys include ways to make and use wheels and axles: Duplos/Legos, Tinkertoys, K’NEX, and so on. Some fun gear building sets include Gears! Gears! Gears!, Quercetti Kaleido Gears and Gearation Refrigerator Magnets. Put these out for free play.

Toy: We also put out this cool Duplo top launcher, already assembled, plus directions on how to build it, so kids had the option of taking it apart and re-building it. (None took that option.) This is a REALLY cool toy. But, the motor skills required to launch a top were more than many of our 5 and under kids could really manage.

Observation

Encourage children to find all the wheels they can in and about the classroom (toy cars and trains, trikes, bikes, door knobs, and so on.) Encourage them to notice how the wheels work. One thing to notice is that with some things, the axle is fixed to the wheels and rotates with the wheels. But, in other cases, the axle is stationary and the wheels rotate around it (e.g. a skateboard).

Exploration: This post focuses on showing the difference between how balls roll and how wheels roll by making a set up wheels and axle from a Styrofoam ball: http://www.littleblastblog.com/2014/09/wheels-center-of-ball.html

Art and Crafts

Game Spinners

We’ve made game spinners. We punched a hole through the center of  paper plates, and a hole in the center of popsicle sticks. Kids decorated the plates however they wanted to. We took a brad (paper fastener), threaded it through the stick, then a washer, then the plate. We spread out the arms of the brad on the other side of the plate, and taped them in place. Poof – it’s a spinner. (The stick is the “wheel” rotating on the brad axle.)

Craft – Tops to Spin

We made tops with dowels and wooden wheels. If you don’t have wooden disks, you could use cardboard. Use a pencil sharpener to sharpen one end of the dowel. Add the wheel. If it doesn’t fit tightly and falls off, just wrap a little tape around the dowel below the wheel. Kids could decorate if they chose, and then play with for as long as they wanted to. (I have to be honest… I’m not sure if tops count as simple machines – are they wheels on axles? screws? neither?) Learning how to spin a top is a good small motor skill.

Craft – Pinwheels. Last year, we made pinwheels – learn about them here.

Art – Paint with wheels! You could use paint rollers, or a massage tool on wheels, or toy cars, or toy trains to paint with.

Media

Song: The Wheels on the Bus, of course! Another option is Bumping Up and Down in My Little Red Wagon, which includes the words “One wheel’s off and the axle’s broken.”

Books: We had several books from series about Simple Machines. We read in circle Pete the Cat: The Wheels on the Bus by Dean and Going Places by Reynolds. You could also check out Rolling Along – Taylor and his Wheelchair by Heelan, and Mr. Ferris and his Wheel by Davis.

Videos: Sid the Science Kid: The Broken Wheel. Or here’s a couple short intros to wheels: https://www.youtube.com/watch?v=YIV9IUHqW3A and https://www.youtube.com/watch?v=vYoWCn5r3rQ

Key concepts of wheels and axles:

When you try to push a load across the ground, there’s a lot of friction that makes it hard to move. The whole surface area of the load is on the ground. When you put the load on wheels, then there’s only friction on the very small part of the wheel that is touching the ground at any given time. Thus, it’s much easier to move a heavy load over a long distance.

A demonstration for Circle Time:

We loaded up a basket with bags of dried beans for weight. We had our 8 year old teaching assistant push it across the ground. Then we showed everyone the rough surface on the bottom of the basket. Then we showed them the smooth bottom of a cardboard box. We placed the basket in the box, and pushed it across the ground. Much easier! Then we talked about friction.

After that, we laid out several short lengths of PVC pipe on the ground and put our box on top of them and showed how much easier it was to move the box back and forth. (Just roll a very short distance back and forth.)

We talked about the idea that ancient Egyptians may have used a similar method to move the large stone blocks used to construct the pyramids, and showed them a picture of this process.

We then tried to move the box a long distance on the dowels. The kids discovered that as you do this, the load rolls off of the dowels, and you have to move that lost dowel back to the front of the row over and over.

(Note: I got this demo idea from Little Blast blog, but we worked on a carpeted floor instead of hardwood, so there’s lots of friction. We used a basket instead of a smooth box – again, this increases the friction so better illustrates the benefit of the dowels. There’s also a nice post here on using a brick and pencils to illustrate this concept.)

One child got the idea of taping the pipes to the bottom of the box. We did, to show why this doesn’t work. (The pipe wheels no longer rotate.)

Then we taught the idea of wheels and axles, and mounting the load on a set of wheels and axles. There’s lots of ways you could do this… We used the wagon from our Simple Machines Set, but you could use any car or wagon to show what wheels and axles are.

Then we placed our basket of beans in a box with wheels on it (see above) and had our assistant pull it all around the room to show how much easier that is to move.

Here’s another great idea for a demo: put a grown-up on a board. Put the board on two scooters or skateboards and push the grown-up around. http://www.littleblastblog.com/2014/09/wheels-make-it-easier-to-push-daddy.html

For a wheels theme, you could obviously do LOTS of activities related to cars. We did a whole week just focused on cars as a complex machine. You could use almost any of these car ideas in a session on wheels.

There’s lots of other great ideas for wheels and axles activities here: http://iijuan12.hubpages.com/hub/wheels-and-axles-lesson-plan-in-simple-machines-unit