This activity provides an exciting and colorful chemical reaction that students can hold in their hands. It’s a great activity for the first couple of weeks of science class as it requires easy prep, any easy procedure to follow, and a fun and interesting phenomena for students to practice making good observations and asking questions about empirical evidence. You'll need calcium chloride pellets (for pools from the hardware store), baking soda, phenol red indicator, small beakers, teaspoons, an