1) why do we add salt to the ice? To make the ice stick together.
2) why do we add the cookies and other things, only after the milk has frozen slightly? If we add it when the milk is not frozen. The cookies won't move and it will be very hard.
3) what are two factors that affect the freezing you think? Salt and ice.
4) why do you need a bit of air in the bag? So the milk can move around easy