Later experience teaching my own science class, Dunbar-Pulaski Middle School.  The year is 2006 and my teaching style is adjusted to make learning more fun, but just as relevant for students.  We demonstrated how salt lowers the freezing point of water.  The same process crews use to melt winter ice on streets and highways is the same process we used to make ice cream.  Heat energy is drawn away from whatever surface comes in contact with the salted ice.  Draw enough heat energy from a milk solution and ice cream is formed.