Someone else besides Gretchen is a math genius, and through math, Gretchen starts a close relationship with this person.

The main kids discover that Gus was once a notorious dodgeball player who went by the name of El Diablo.

A career day assembly gets all the kids to decide their future careers. That is all except Spinelli.

Every year the older kids pick kindergarteners to race in the Kindergarten Derby. This year an eager Tubby gets an unwilling Mikey to sponsor him in the race.

Fed up with Vince's ego, the kids bet Vince that he can't go one whole day without beating someone in a sport.

T.J. takes charge when Gretchen seems to achieve a dream that T.J.'s always had, to be an astronaut on the space shuttle.

Randall becomes popular when he uses a joke book to make himself a standup comedian.

T.J. shows up in school with a black eye. Everyone makes up wild stories about the heroic acts T.J. must have done to get the shiner.

T.J. breaks his clavicle and now has to spend recess with the ""pale kids"" in Room 51.

Spinelli gets a crush on a fifth grader and has to get over it to save her reputation.

In his hatred of Valentine's Day, T.J. sends a ""funny"" valentine to every single girl on the playground to show them how stupid Valentine's Day is, but his plan soon backfires when the girls mistake them for ""real"" valentine cards.

T.J. and Vince are so into the "Barnaby Boys" books that they dress up like the Barnaby Boys and try to solve the mystery of the suspicious substitute janitor, Earl Raymond.

TJ receives an old history textbook with a treasure map that leads the gang, Randall, and the Ashleys out to get the treasure. But as they get closer, greed arises and the 4th graders fight for the treasure.

When the gang catches the mysterious ""Libray Kid"", they take her out to recess where she becomes obssessed with the playground.

Everyone is segregrated once the Ashley's start giving ratings to everyone on the playground.