Backyard science: How to make your chalk drawings fizzy

A useful bit of knowledge to have under your belt is that baking soda plus vinegar produces a gentle fizz. This chemical romance is the premise beneath volcanoes you may have produced at a science fair as a child. And if you were deprived of that pleasure, well, there’s no time like the present.

I bought enough of both baking soda and white vinegar to keep some with our outdoor toys so it could become an activity the kids occupy themselves with in the backyard. I didn’t exactly have a plan. Since my kids have outgrown our water/sand table, I was thinking we could do something different or weird with it, like use the compartments for different experiments. Unfortunately, cleaning the old wet sand out of the table turned out to be too much of a hurdle for me, and I am still hoping a magic fairy comes to my backyard to take care of that for me someday.

The activity that evolved was first making chalk drawings, then sprinkling baking soda on top of them and squirting vinegar to watch them fizz.

Julian loved rubbing his hands around in the results, and the materials are non-toxic, so, whatevs. Eventually, Scarlett felt that simply sprinkling baking soda on a rock and pouring vinegar on top of that was the most satisfying thing. Who am I to judge?

In this video, my kids share their project with you.