From Muppet Wiki

Win Some, Lose Some is a Muppet Kids storybook.

Piggy, Fozzie, and Kermit are playing Basketball with a gift from Fozzie's Aunt Minnie. Each day they play they get a little better. One day a new kid named Kevin asks to play. Instead of playing for fun, he convinces the kids to play a real game, showing bad sportsmanship the whole time. In the end the kids convince Kevin winning isn't everything, and it's more important to have fun during the game.