Rainbow – Science for Kids

rainbow science for kids

At this week’s Family Inventors Lab, our theme was Rainbows and Color Mixing. This followed last week’s session on Light and Shadow and we were able to reflect back on what we learned there about light reflection and refraction, and extend it here.

In this post, I include:

  • Science exploration: shaving cream rainclouds, capillary action, draw what you see, and color mix with light
  • Art projects: Rainbow tops, bracelets, and butterflies
  • Art process: Rainbow mural, paper marbling, rainbow paper, color mixing
  • Free play: rainbow shadow screen, light table, sensory tables, bubbles
  • Circle time activities: songs, games, and books

Let’s start with our challenge activity:

Science Tools – Build a spectroscope.
Last year, we built  spectroscopes from paper towel tubes, tapes, and old CD’s. (Read here about what we did, or go to my source for the idea – Buggy and Buddy.)

This year, we used Rainbow-Scope Kits. You can read all about them in my review of Rainbow-Scopes. It was a fun, do-able project for all our kids, with nice results.

spectro-header  img_20170116_180805676   img_20170116_184145494

Science Exploration

Shaving Cream Rainclouds: We “made it rain” by filling a big container with water, spraying shaving cream on top, and using pipettes to drip diluted liquid watercolor on the shaving cream clouds. It slowly drips through, creating swirling “rainfall” below. For more pictures and thoughts on talking to kids about the science of rain, check out this post. Be sure to get shaving cream, not gel. One can was enough for 20 kids worth of experiments, but I always buy two cans, just in case. If there’s leftovers, it’s great for puffy paint. (Mix equal parts glue and shaving cream for a fun 3-d paint – great for collages!)

IMG_20160430_104802937  a photo of a tub of water with shaving cream on top

Rainbow Capillary Action. Put out 7 baby food bottles, in this order: red water, empty, yellow water, empty, blue, empty, red. (Use liquid watercolor or food coloring to color.) Prep paper towels – fold in eighths or so…. When class begins, place paper towel bridges. The water wicks up the towels and color mixes in the empty jars. http://www.kidsneedenrichment.com/capillary-action/

Draw what you see: We had diffraction grating peepholes. When you hold these up to your eye, then look at a light, the light is broken up into rainbows. Different lights produce different patterns… ambient light may create spread out rainbow colors. Looking at a ceiling light, you might see circular rainbows; an LED flashlight on a cell phone can create six rays of rainbows radiating out. (Learn more about diffraction lenses here. Sorry that it’s a marketing post where they’re trying to sell a product… but the site does do a nice job of describing how these lenses work.) This photo is a view of our overhead projector image from above, seen through the diffraction grating:


We also put out kaleidoscopes, our spectroscopes, and prism viewers for them to look through. We had crayons / markers and paper out so the kids could draw what they saw. It might also be fun to give kids a camera and let them take pictures of what they can see. You’d need a camera with a small lens (like a cell phone) to line up with viewing holes on things like kaleidoscopes.


CD Rainbows. If light reflects of a CD, it can create rainbow patterns. (Learn why.) You can do this in sunlight or by shining a flashlight. You can add fun patterns with paper snowflakes: http://buggyandbuddy.com/rainbow-science-create-light-patterns-with-a-cd/

Color mixing light with water: We had jars of colored water and a bright light to shine through them. We used a mirror to reflect the light to “mix” colors. This experiment was not yet a success. We needed a flashlight with a really tight, bright beam, not a broad angle shop light, and we needed a darker space with less ambient light.

IMG_20160430_101130244  IMG_20160430_104750580

Color Mixing Lightbulbs. I built this lightbox which uses colored LED bulbs and dimmer switches to mix light. Learn more here.

Art Projects

Rainbow Tops. Last year, we tried Rainbow Button Spinners. We weren’t happy with the results – the kids could color the wheels, but the parents had to do all the assembly, and then they weren’t heavy enough to spin well. Might be good for 6 – 8 year olds, but not a good match for our 3 – 6 year olds. This year, we did tops – built a top with a metal washer and a dowel, then added the paper rainbow disk. When you spin it, the colors all blur together.

Rainbow butterflies: We used eye droppers to drip liquid watercolor onto coffee filters, which creates some beautiful color mixing. (Don’t dilute the liquid watercolor – use it straight.) Then we used clothespins to turn the coffee filters into butterflies. (I like the old-fashioned clothespins a little better than the spring-loaded ones for this project.) Add googly eyes (or draw on eyes) and pipe cleaners to finish the project.

I didn’t get a picture of our butterflies, but here’s a sample of what they could look like. (Source for idea)

Picture from Thoughtful Spot Day Care
Picture from Thoughtful Spot Day Care

Beaded Rainbows or Bracelets: We had elastic and pipe cleaners and beads out and kids could choose to make a patterned bracelet, or choose to make rainbows on Styrofoam bases. This year, we got photo-sensitive beads – they look white in indoor light, but if UV light from the sun or a black light shines on them, they turn bright colors. I bought this product, whose photos show the beads turn most of the colors of the rainbow. The reality was they were pink and purple and clear. So, not a rainbow, but still really cool, and I would absolutely use them again in the future, maybe in this class, maybe in light and shadow. (Or my favorite Amazon review is of a parent who was tired of battling her child about sun screen, and they made the deal that if her beads didn’t change color outside she didn’t need sunscreen, but if they did, she did.)


Salt Painting. You can make colored salt and sprinkle it onto glue for a really pretty result. Learn how.

Art Process

Group Mural: The first year, we had a painting of a rainbow on the wall, then had a black and white line drawing of a rainbow below that they painted in to match the one on the top. The second year, we offered a drawing of a rainbow and colorful post-it flags to fill it in. (Post-it flags are a good small motor skill builder. Buy them at a dollar store, don’t pay office supply prices!) It was easier to set-up and clean-up, but not as satisfying a project, so for the future we went back to painting, just drawing an outline of a rainbow and adding a color dot and a label onto each stripe so they knew the color to paint that stripe. We also had the easel next to it for anyone who wanted to paint their own rainbow to take home.


mural rainbowmural

Marbled Paper. After you do the shaving cream rainclouds described above, you can gently swirl the shaving cream around (be gentle – it will continue to float on the water if you do it right), then lay a piece of paper flat on top, press it down (slowly but firmly so it takes in the color but doesn’t sink under water). Then scrape the shaving cream off the paper, and you have marbled paper! Learn more about shaving cream paper marbling.

paper that was marbled with shaving cream

Rainbow Paper. Set out a bowl of water, clear nail polish, and some black paper. Drip a few drops of nail polish onto the water – it disperses. Immediately dip in a piece of black paper. Pull it out. Set to dry. In a few minutes it will be covered with rainbows – looks sort of like an oil slick. www.sciencekiddo.com/rainbow-paper-kid-color-science/  (Note – if you don’t work quickly, polish dries on top of the water – just scoop film off and try again)

Different types of nail polish yield different results – that’s Sally Hansen top coat on the left, and Sally Hansen hard as nails on the right.

photo of opalescent paper

Color Mixing. You could take a clear container with lots of compartments (like a clear egg carton?) and give the children liquid watercolors and pipettes. They can mix different colors in different compartments to see what they mix up into. This would be fun on the light table.

Free Play

Shadow ScreenWe had an overhead projector, so we set it up with our screen from last week’s Shadows class. We put out a wide variety of colorful items that could be set on the projector and seen up on the screen. We also had a top that kids could spin on the projector and see the spinning shadow. This activity was a big hit.

IMG_20160430_104940846  IMG_20160430_110828373  IMG_20160430_104914997

This projector idea was from a children’s museum we visited somewhere on our travels. They also had x-rays that kids could project on the wall, and these cool wood blocks with translucent shapes.

Light Table. We put colorful translucent items on the light table. After I took the picture, we added Color Paddles which are fun for color mixing.


Writing tool: We made a rainbow tray, like in this Nurture store activity, with the intention of filling it with salt for kids to practice drawing letters in. But, we discovered we didn’t have salt in the classroom. We tried flour, which I’ve used successfully with one toddler but in the classroom setting with multiple kids, it was too messy. We tried white plastic beads (like you fill beanbags with) but they were too messy. We tried rock salt, but you couldn’t effectively trace letters in it. So, we’ll try again next time.


Other Ideas: Other activities we’ve used for this theme were magna-tilesrainbow crayons, rainbow colored blocks, rainbow puzzle stacker, a sensory table filled with colored rice or pasta or other colorful items, a water table filled with water beads of other colorful items, a rainbow water xylophone. We had blocks of ice that they could sprinkle salt onto and pour water onto, and drip liquid watercolor on to help it melt. Even better would be to make rainbow colored blocks of ice. We also had a rainbow colored tumbling mat with colored hoops to jump into for some big motor play. We played a little spontaneous Twister on the mats: Put your left hand on the red part, put your right foot on the blue part, and so on.

blocks  sensory-bin

One year we tried color your own playdough, where we gave them balls of white playdough and they mixed colors in. (We used liquid watercolor for this, which was not a good idea as it made the playdough too wet. We may try again in the future with gel or powdered color.)


Rainbow Songs

There are so many songs about rainbows! I made a playlist of rainbow songs and we just had it playing in one room while kids played.

Circle Time

Gathering Song: For our gathering activity, I gave all the kids colorful scarves, and told them that when I called their color, they should wave their scarf, and when I said “rainbow”, everyone should wave their scarves. We practiced that, then I put on this song, and we waved our scarves. Note: it was hard for our little ones to keep up with the speed of this song, so another one from the playlist might work better if you’re working with 3 – 4 year olds. I prefer: www.youtube.com/watch?v=HQGA1_PR4Aw

Understanding the Big Idea: You could choose to show a simple video, such as this one or this one:

I just talked about rainbows, asking questions – the older kids knew these answers:

  • “To see a rainbow outside, you have to have a specific type of weather – what do you need?” We discussed sunlight and rain. I explained that you see a rainbow when the sun is behind you, shining on water droplets in front of you. (This ties into what we learned last week about how when the sun is behind you, your shadow is in front.)
  • “What are the colors of the rainbow?” We wrote them on the board, and I explained that all rainbows always have the color in that order. (I told them about Roy G. Biv mnemonic.)
  • I reminded them that last week we learned that if light shines straight at a mirror, it bounces straight back (reflects). But we also learned that light can bend (refract) when it passes through water. I drew diagrams on the board showing this. (Note: this would also be a good opportunity to read another great Vicki Cobb book called I See Myself which is all about light reflecting.)
  • Then I showed them the flashlight on my phone and asked what color the light was – white. I told them it was made of many colors, and if we could bend the light, we could see all those colors.
  • We turned out the light, I held up a glass of water, and shone the flashlight through it to make a rainbow. (Note: be sure to test out a variety of glasses to see which gives the best rainbow effect – I had the best luck with a stemless wine glass, and shining my light through the curve at the bottom.) I also showed how the reflection off a CD can create a rainbow, and how a prism creates a rainbow. (With each, I pointed out the order of the colors.)
  • Sunlight (and most lights) are made up of several colors of light. When a ray of sunlight hits a droplet of water it bends. Each wavelength bends at a slightly different angle, so they separate out by color. (I add this to my diagram on the board.)

Book: We read A Rainbow of My Own by Freeman. It’s a nice story of a boy who imagines having a rainbow follow him and play with him, but then his imaginary rainbow disappears. When he goes home, he finds a “rainbow of his own” in his room as the sunlight shines through the goldfish bowl, creating a rainbow. It’s a sweet story, and our kids totally got that real rainbows don’t behave like his pretend one did, and they liked that it ended with the rainbow and the goldfish bowl, which echoes the demonstration we just did.

Song: Barney’s Rainbow Song: https://www.youtube.com/watch?v=wbF3-vk1s6s

Oh, I like red, it’s the color of an apple. Orange, it’s the color of an orange.
Yellow, it’s a lemon, and a wonderful sun, sun, sun.
Green, is the color of the trees, and lots of things that grow.
And then there’s blue for the sky, And purple, that’s a color that’s fun, fun, fun.
And when we put those colors side by side, Now, what do you think we’ve done? We’ve made a rainbow, and it’s a really beautiful one, one, one.

There’s some other nice song options on Preschool Express and on Perpetual Preschool, or on the YouTube playlist I mentioned earlier.

Closing Circle: We sometimes read Planting a Rainbow by Ehlert, about planting a colorful garden. It ties in nicely to this week’s rainbow theme and an upcoming Seeds and Plants theme. Sometimes, on the color mixing theme, we read Mouse Paint.

Then we got out the parachute (it’s rainbow colored) and played the song Somewhere Over the Rainbow by Israel Kamakawiwo’ole. We waved the parachute up and down gently with kids under it. We put balls on top of it and bounced it wildly, and we played a variation of Red Rover under it. (When I called Red, everyone holding onto a red part of the parachute had to let go, run under the parachute to another spot on the parachute.)

Rainbow Books (contains affiliate links)

  • Rainbow by Bauer and Wallace.  A simple non-fiction read-aloud that overviews the basic science of rainbows. Good for a preschool STEM class.
  • Take a Walk on a Rainbow – A First Look at Colors – a fine non-fiction book about science, rainbows and colors.
  • A Rainbow All Around Me by Pinkney. What I like: photos of kids painting rainbows, brightly colored photos for each color. What I don’t like – I find it doesn’t flow well for me to read out loud. It does some colors, yellow, blue, red, then a little refrain of “colors are you. Colors are me.” Then orange, purple, black (not in the rainbow). Refrain. Green, pink, brown (yeah, also not in the rainbow…). Refrain. White, tan, ending page…
  • I Am a Rainbow by Dolly Parton. A feelings book. Talks about when we’re tickled pink, seeing red, feeling blue, green with jealousy, scared yellow and when everything is rosy. Nice little book about emotions but my 5 year old wanted to know why it didn’t include orange if it’s called a rainbow book.
  •  Rainbows Never End: and other fun facts by DiSiena and Eliot. A science trivia book for ages 6 – 7. A couple pages on rainbows, and more on snow, rain cycle, thunder and lightning, tornadoes, solstice, the North and South pole, deserts. and so on. A good general purpose collection of “fun facts”.
  • Rainbow Shoes by Stone and Czernecki. A collection of silly poems, each tied into a color. Do Robots wear red rubber boots? Orange socks. Purple pants poem, my underwear is dingy and so on. Fine for a poetry unit, not really for a STEM class.
  • Elmer and the Rainbow by McKee. There’s a rainbow in the sky that has lost its colors. Elmer goes on a quest, and then shares his colors with the rainbow. I’m all for fantasy (see “A Rainbow of My Own” that was my favorite for this week) but this book managed to just be too scientifically inaccurate for my taste.
  • Curious George Discovers the Rainbow adapted by Cherrix from a TV episode. Really wordy in the main text – maybe suited for 6 – 7 year olds, plus lots of wordy side bars of additional facts. The content is good – there’s just a lot of it.
  • The Invention Hunters Discover How Light Works by Briggs. Intersperses a fun and silly story of “invention hunters” who are wrong about everything (they see a prism, and guess that it’s an ice cube or a necklace or a yeti’s tooth) and a child who shares the correct scientific information. “A prism bends light and makes rainbows. Light is made up of tiny little things called photons that are launched from the sun… and anything else that produces light… a glass prism bends light, but it bents some colors more than others…” The sales listings for this book say that it is for ages 4 – 8. Though the silly parts would engage a young child, the science descriptions are really more appropriate for 7 or 8 year olds.
  • Weaving the Rainbow by Lyon and Anderson. Pretty watercolor illustrations, and a story about raising lambs to adulthood, shearing the sheep, spinning the wool, dyeing it with goldenrod and madder, and weaving a pastoral picture. Would be a good book to accompany a class in the traditional arts. (Waldorf style.)
  • Maisy’s Rainbow Dream by Cousins. If you have a Maisy fan, they’ll love this book, which is full of lots of big, bright, colorful illustrations. I don’t love it. The page says something like “Maisy dreams about an orange fish.” And there’s a picture of an orange fish, but also a panda bear / mermaid and an alligator on an airplane, a squirrel in a boat and a ladybug. Who knows why. Ages 3 – 4.

Rain Books. If you’re talking about rain as well as raindrops, here are some good options.

  • Raindrops Roll by Sayre. Absolutely gorgeous nature photography combined with a nice read-aloud about rain for preschoolers. Lovely.
  • Who Likes the Rain by Etta Kaner. Nice non-fiction.
  • What is the Water Cycle by Ellen Lawrence

Videos: There’s a Sid the Science Kid episode called What is a Rainbow. It’s available to stream for a fee on Amazon, but I have not found a free version. Also, check out the links above in the opening circle section.

We always have more ideas than we have time and space for, but if you’d like more ideas for rainbow-themed activities, look on our Pinterest page: https://www.pinterest.com/bcparented/rain-and-rainbows/

Affiliate Links: In my posts, you’ll see lots of links to products on Amazon. I do get a “kickback” – a referral fee if you click through and buy these products. However, my primary goal is to make it easier for you to find the materials, or sometimes just to illustrate what I used. For example, in my post, I don’t want to spend a lot of time describing the best brand of shaving cream to buy at your local drugstore. It’s easier to put an affiliate link to the Barbasol on Amazon so you can see what I used, and you can know whether that’s something that’s easy / cheap for you to pick up at a local store.


  1. […] Rainbows. Colorful food: Could do rainbow goldfish, or graham crackers with rainbow chip frosting, or could do fruit skewers where they’d put colorful fruit on a bamboo skewer in rainbow order (red watermelon, orange orange, yellow pineapple, green kiwi or honeydew, blueberries, purple plum or blackberries.) […]


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