The Other Me (2000)

"Holy 'A' in Science Class - I made myself clone!"

When Will Browning is threatened with military summer school if he doesn't get better grades, he decides to do a science project that will definitely get an A. So he buys some Ocean Pups, unhatched sea creatures that will look spectacular, but he hasn't bargained for the cloning agent that the unscrupulous manufacturers have put in the kit. Next thing he knows there's another him.