An 11-year-old boy named Greg (Zachary Gordon) is just starting middle school. He is very excited about the possibility of becoming one of the "cool" kids. He has an "uncool" friend (Robert Capron) who he feels is getting in the way of that. Throughout the film Greg tries to become "hip" by doing various things, such as joining the school sports teams and signing up for school clubs, but most of the results are comedic. Along the way he is laughed at by his older brother Rodrick (Devon Bostick) who feels like no matter what, Greg will never be cool, and he should just accept that.