Attack of the Mutant Underwear

At a new school where no one knows him, Cody Lee Carson has resolved to become cool—but as it turns out, that may be harder than he thought
Cody Lee Carson is a changed man. When his parents move him to Benton, Oregon, for his fifth grade year, Cody is determined to stop being his boring, bozo-brained old self and start being the supercool, supersmart, superawesome guy he knows he can be—especially since no one in Benton knows about the incident in fourth grade when his pants fell down during a school play and everyone saw his Tweety Bird underwear. And Cody's plan works! His new teacher loves him, he gets in the top reading group, and the prettiest girl in class wants to be his friend. It seems like everything is going Cody's way.
But when the old, bozo-brained Cody starts slipping out, will he lose everything he's worked for? Becoming cool was easy, but staying cool is a little more difficult.