The document provides instructions for making ice cream using a ziplock bag method to demonstrate changes in state and energy transfer. Volunteers are needed to run the ice cream making stations using ingredients like milk, sugar, and flavoring sealed in a small bag within a larger bag of ice and salt. Through massaging the bag for several minutes, the mixture is cooled by the ice until it transforms into ice cream as energy is transferred and its state changes from a liquid to a solid due to the endothermic melting of the ice.