This activity was intended for my toddler, but it turned out to be my kindergartner’s favorite part of the day. Since there’s some STEM involved, keep it in mind if you find yourself home schooling!

For set up, I wanted Veronika to have the option of color mixing, so I filled three cups with vinegar. I left one clear, added yellow food coloring to the second, and blue food coloring to the third.

I then sprinkled a box of baking soda into a shallow tray. Veronika instantly liked making lines through it with the pipettes I had left out. It was sort of like an indoor sandbox for a moment.

Then it was time to start squeezing in vinegar! I used the clear cup first, knowing the bubbly reaction was enough to get a “wow” even before we added color.

Then we started piping in the colored vinegar. I had hoped Veronika might get in some fine motor practice with the pipettes, but that was too much for 16-month-old fingers. Big brother Travis loved using a pipette and baster, though! Then the kids poured the cups of vinegar instead, for even bigger reactions.

The blue and yellow turned into a nice green, of course, which I’d also hoped to demonstrate.

After that we just had a big pile of green bubbly “lava” that the kids loved scooping through with pipettes and cups for ages.

Eventually they wanted to drip in other colors from the food coloring set, which was fine, although it didn’t look so pretty.

A great afternoon activity!