Movin' on Pup is the first half of the third episode of from Season 1. It was directed by Teacher's Pet Timothy Björklund and written by Bill and Cheri Steinkellner.
Scott does so well on the N.A.S.T.Y. test that an impressed Principal Strickler promotes him to the fifth grade, but Scott finds out that the fifth grade is much more of a challenge than he had anticipated.
Moral: Don't be in a rush to grow up.
Strangely, the fifth graders look like and do the same work as high school kids. This was most likely done to illustrate the difficulties of being promoted a grade ahead.
The fifth grade bullies, Max and Miles, along with their classmates, would later been seen in other episodes (Dogfight), or randomly placed in the background (The Flipper, Bad Fur Day, etc).
Disney's Teacher's Pet Episode Three Part One- S01E03A - Movin' On Pup