Double foul

"Mack, Andre, and the gang are back at . . . [Camp Average--er, Avalon] for another summer. For the first time, the camp is open to girls, including Mack's friend, Nicole. Plus, kids can actually choose if they want to play sports competitively or not. Which means Mack can enjoy the waterfront, while his nemesis, Winston, the camp director, chases trophies. Not that Camp Average has won any. The season is more than half over, and they've got nothing to show for it. That's when Winston makes one final attempt to fan the camp's competitive flames by pitting boys against girls in a basketball showdown that turns ugly. What's worse, all the camp's noncompetitive activities start mysteriously shutting down, including Mack's beloved water sports. He smells a rat . . . one that wears red short shorts and knee-high socks. Will Winston ruin everyone's summer again?"--Provided by publisher.