Marissa is a gymnast, violinist, and chess player. This summer she is busy in an orchestra, chess tournament, and learning her Level 4 gymnastics skills.In the past, doing all three activities has been a snap for Marissa. She is hardworking and smart. But this summer she can't seem to get her kip, a difficult skill on bars. If she doesn't learn a kip she won't be competing Level 4 in the fall with her friends at Perfect Balance Gymnastics Academy.As...