The Fairly OddParents (2001)

Timmy thinks Cosmo and Wanda have it easy being godparents, and vice versa. To prove each other's points, Timmy becomes a fairy and Cosmo and Wanda become normal kids. But Timmy can't control his magic and has to undergo training from Jorgen von Strangle, and Cosmo and Wanda have a tough time dealing with Timmy's parents and school.