What trademark laws would I need to abide by if I wanted to put "I (lion's paw) Penn State" on balloons?

The balloons will be purchased solely for my own personal use to remind me of my years at Penn State after I graduate in May 2010. After that date, whenever I feel sad about missing Penn State, I can grab some of the balloons, get in my car, drive to a dollar store, and get them inflated with helium. I do know that I will neither make any profit from this nor will I intend to sell them.