premise: How to make ice cream without an ice cream maker.
hypothesis: Gather ingredients- 1 cup heavy cream, 1 cup half and half, 1/2 cup sugar, 1 teaspoon vanilla extract, 2 gallon sized resealable plastic bags,  2 cups ice cubes and 1/2 cup salt. Pour cream, half and half, sugar, and vanilla extract into a gallon sized resealable plastic bag. Seal well. Squish it around to combine until sugar is dissolve, place ice cubes and salt into another gallon sized resealable plastic bag then ad ice cream mixture into the bag with the ice, seal and shake about 5-7 minutes and you have ice cream.