Tina's ready to play in a big way after getting her cast removed, and the kids suggest staging a playground circus. Michael, the Ringmaster, introduces Barney, the Balancing Dinosaur; Derek, the Juggler and the Tightrope Twins, Terrific Tina and Magnificent Min. Special Guest Joe Scruggs sings the song that really sets off the silliness, but, in the end the kids learn that exercise is good for your body and can still be lots of fun. Barney also reminds us that hugging is an exercise that's good for the heart!