This is a really simple science experience for preschool age children. (It’s also an art experience and great small motor practice. It’s easy to set up, easy to clean up, and inexpensive. Like so many chemistry experiences, it goes through a lot of baking soda and vinegar…. but less than making volcano after volcano does!
Fill a shallow tray with a thin layer of baking soda. (Or use a muffin tin and fill each cup with a little baking soda.)
Then mix vinegar with liquid watercolors or food coloring. We make small cups of 3 primary colors so they can also explore color mixing.
Let the children use pipettes, eye droppers, or spray bottles to drip colored vinegar on the baking soda and watch it fizz. Several children can do this side by side.
When you’re done, just rinse it all down the drain.
You can find lots more hands-on chemistry experiments here.