- Gather a bucket full of water and dump in sand.
- Form a mountain with the sand. Make sure it has a pointy peak. See below photo.
- Using your finger or a stick, poke a hole into the center of the peak that is a few inches deep.
- Scoop 2 spoonfuls of baking soda into the hole.
- Pour 1/2 cup of white vinegar into the hole and watch the science begin!

Bonus: Add red food coloring to the vinegar before dumping it into the hole.
Further investigation:
- What happens if you put the vinegar in the hole before adding baking soda?
- Will it work the same if you use water as the liquid?
- Can the volcano be built with dry sand? Why?