Baking Soda Volcano

Baking soda (about 1/4 cup)

White vinegar (about 1/4 cup per eruption)

A squirt of dish soap

Food coloring (red and yellow look most like lava)

Small cup, jar, or empty plastic bottle

Baking tray, large dish, or do it outside

Spoon for stirring

Place your cup or bottle in the center of the baking tray.

Add 2-3 tablespoons of baking soda to the cup.

Squeeze in a small squirt of dish soap (this makes the fizz foamier).

Add a few drops of food coloring on top of the baking soda.

Let your child pour the vinegar into the cup. About 1/4 cup is enough for a good eruption.

Watch it fizz and overflow!

Ask them: "What do you see happening? Where are the bubbles coming from?"

To erupt again, add more baking soda and pour more vinegar. You can repeat this as many times as you want.

Baking soda is a base and vinegar is an acid. When they mix, they create a chemical reaction that produces carbon dioxide gas — that's the bubbles!

The dish soap traps the gas in bubbles, making the eruption foamier and more dramatic.

This is the same kind of gas that makes soda fizzy.

Do this on a baking tray indoors or take it outside. It gets messy, but it's just vinegar and baking soda so cleanup is easy.

Let your child control the pouring. Preschoolers love being the one who "makes it go." The more ownership they have, the more they learn.

Try experimenting: What happens with more vinegar? Less baking soda? Warm water instead of vinegar? Let them guess before trying.

Add a few drops of different food coloring each round to create different colored eruptions.

This activity can repeat 5-6 times before you run out of baking soda. Buy the big box — it's worth it.

For extra fun, build a volcano shape around the bottle with play dough or damp sand.