This Melting Rainbow preschool science experiment is perfect for preschoolers and kindergartners. It's easy to set up and uses common household items.
Does your kid ask “why” a gazillion times a day too?
Little kids are naturally curious about how the world works and are budding scientists – even if they don't know it!
Rainbow-loving kids will adore this simple preschool science experiment where they can melt a rainbow. They'll also love observing this pink fizzy bath bomb Valentine experiment.
Don't forget to check out our 30 Day Science Activity Plan for even more science experiments for kids.
Why is Preschool Science Important?
Doing preschool science activities are a lot of fun, but they are also full of wonderful learning opportunities.
Introducing science at an early age is important for many reasons. Working on preschool science experiments helps little kids learn how to research, problem solve, and communicate.
It also creates a foundation that encourages kids to continue their education and join science based careers.
Introduce young kids to the basics of chemical reactions and a rainbow of color with this fun science activity that also helps build fine motor skills and boost hand muscle strength at the same time.
What I love about this science experiment for kids is that it is easy to set up and uses a few simple ingredients found around the house.
Don't be surprised if your kids ask to repeat this experiment over and over!
Melting Rainbow Preschool Science Experiment
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Little ones will love melting a rainbow with a baking soda and vinegar reaction to make a fun, colorful soup they can play in for hours! You can watch my son and I set up and do this activity here.
After doing this activity, change things up a bit with this Fizzy Bottle Caps Science Experiment.
If you don't have these ingredients on hand, then grab some candy and water to try our science experiment making rainbows with M&Ms.
On nice days, I like setting up this science experiment for kids outside. If you concerned about it getting messy inside the house, you can let the kids conduct their experiment in the bathtub.
Melting Rainbows Science Experiment Materials:
Melting Rainbows Preschool Science Experiment Directions:
Pour a tablespoon of baking soda into six small containers.
Add a few drops of food coloring to each to make the rainbow.
We used red, orange, yellow, green, blue, and purple. Add a squirt of dish soap.
Mix with a fork. The dish soap should be wet enough to mold the baking soda into a ball. But if it isn't, add a little bit of water to each container.
Roll each color of baking soda into a ball and put it on a plate.
Give the plate to your preschooler. Ask them what they think will happen when they squirt vinegar on the baking soda balls.
Then show them how to use the pipette to pick up vinegar and squeeze it onto the baking soda balls, melting the balls and creating a chemical reaction that bubbles and foams.
It can take quite some time to melt all the baking soda, and little ones will love repeating the experiment over and over.
Preschoolers never get tired of baking soda and vinegar reacting and the foam produced is pretty and smells great, thanks to the dish soap.
After a while, the mixture will get soupy and you can move on from science to sensory play.
Though what a perfect way to transition into a color mixing activity!
This is a great activity for preschool and kindergarten children. This melting rainbow preschool science experiment is a great way to practice color recognition and introduce kids to chemical reactions.
Using the pipette to carefully apply vinegar to the baking soda rainbow is a fun way to practice fine motor skills while learning about science too.
More science experiments for kids to try:
- Fizzy Bottle Caps Science Experiment
- Balloon Air Pressure Science Experiment for Kids
- How to Make Galaxy Oobleck
- Unicorn Sensory Bin with Oobleck
- M&M Candy Rainbow Science Experiment for Kids
- Oil and Water Color Changing Lab
Printable Melting Rainbow Science Experiment Instructions
- Baking soda
- Dish soap
- Food coloring in rainbow colors
- Pour a tablespoon of baking soda into six small containers.
- Add a few drops of food coloring to each container to make the rainbow. We used red, orange, yellow, green, blue, and purple.
- Add a squirt of dish soap to each one.
- Mix with a fork. The dish soap should be wet enough to mold the baking soda into a ball. But if it isn't, add a little bit of water to each container.
- Arrange the baking soda balls in a rainbow.
- Fill pipettes with vinegar and squirt vinegar over the baking soda balls.
- Watch the vinegar and baking soda reaction and how the colors look like they are melting.
You may need to adjust the amount of baking soda and liquid. If it's too dry, add a little more water at a time. If it's too liquidy, add more baking soda.