Two excellent video presentations on symmetry. The Ted Talk by Marcus du Sautoy is an excellent introduction to the concept of symmetry and systematically describing it. In "Impossible Crystals" Nobel Laureate and physicist Paul Steinhardt discusses the creation of "Impossible crystals": quasi-crystals with five-fold symmetry previously believed impossible.
Gain an appreciation for symmetry in our every day lives.
The best implementation is to provide the links on a class site such as Blackboard, then heavily promote them. The TED talk is short enought (17 minutes) to be shown in class.
I asked for informal feedback in class. Some students really enjoyed them.
Students approached the Group Theory unit with more enthusiasm. I suspect that this is because I 'set the stage' with the two symmetry lectures, which provide a connection of symmetry to everyday life.