Science can be scrumptious, especially when your experiment results in delicious ice cream. We recently did this project at the Kingston and Little Boston Libraries as the grand finale for our summer STEM programs and it was a big hit.
Enjoying ice cream in the shade of the Port Gamble S'Klallam Longhouse
Here are directions for you do try this at home:
Ice Cream Ingredients
In a quart-size Ziploc bag, mix together:
1-2 tablespoons of white granulated sugar
0.5 cup of half and half (or cream, or milk)
0.25 teaspoon vanilla extract (or coconut, or strawberry, or lemon…whatever flavor you like!)
Double bag the ice cream ingredients in a second ziploc bag
Cooling Mixture Ingredients
In a gallon-size ziploc bag, mix together:
3-4 cups of ice cubes
0.5 cup of rock salt
To make the ice cream, place the small ice cream ingredient bag inside the larger cooling mixture bag and SHAKE for 5-10 minutes. You know you are done when the cream changes from liquid to the consistency of soft-serve ice cream. Open up the ice cream bag carefully to avoid getting salty water inside it, and dig in with a spoon. You don’t even need a bowl!
This project creates opportunities to learn and discuss several scientific principles, such as the effect of temperature on liquid, what is the freezing point of water, and how Soldium Chloride (aka salt) interacts with ice. You can also try different variables and observe their changes to outcomes. Will using non-dairy milk, such as almond milk, work? What if you use table salt instead of rock salt? Could you add chocolate syrup to make chocolate ice cream? Have your kids hypothesize what they think will happen, and then try it out. Happy tasty experimenting!