For this activity you will need 3 matching jars with lids. We used mason jars. Other than that you just need water in various states! Liquid, ice cubes and snow.
Fill the first jar with water and put on the lid. This is your control. We are working on developing our understanding of the scientific method and scientific process, and using controls and controlling variables is part of that process. They must have lids to prevent evaporation. The next jar we filled with ice cubes. Use cubes, not shaved ice. You want there to be lots of air around the ice cubes.
Secure the lid.
Finally, go outside and scoop up snow. Pack the third jar full of snow. I encourage them to pack as much snow as they possibly can into the jar. Secure the lid. Now set the jars in a safe place to see what happens as they melt.