Here's a way to bring science to your backyard sandbox!
Use a pringles can or a bucket and build a volcano shape around it.
Fill your core (the can or bucket) about halfway up with sand.
Add baking soda to fill the rest nearly full.
Throw in some food coloring to add some color to your "lava."
Let the kids pour vinegar in to the top of the volcano and let the eruptions begin!