After learning about transfer of energy, specifically the loss of kinetic energy to friction, students get a chance to test friction. In groups they are given a wooden block, different fabrics, and weights and asked to design the "best" puck. The class first needs to define what makes the "best" puck. Each group should realize that the most desirable puck will travel the furthest, thus the puck with the least amount of friction. In the context of hockey the "best" puck is the one that travels farthest and loses the least kinetic energy to friction. Students then need to apply their knowledge of friction to design a new optimal puck for the National Hockey League. The friction is the transfer from kinetic energy to heat energy.