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.
Darcy lives outside of Milwaukee, Wisconsin with her husband, their 8 year old daughter, 6 year old son, two cats, and a rescue dog. She loves to share kids crafts, simple recipes, and parenting tips to help other moms. She's passionate about education (which is why she is a PTO board member and Box Tops Coordinator) and all things babies. Darcy loves purple, geek culture, and making an ordinary life feel extraordinary. She and her family enjoy exploring Wisconsin and planning local adventures. Author of Breastfeeding 101: Beauty in Breastfeeding, available on Amazon. Her writing has also been featured on Babble, CafeMom, and Mom.me.