The Fitness Zone program was an organization to enforce fitness for students. It associates with P.S. 38, and likely several other schools..
Immediately after the initiation of the Fitness Zone, changes begin in the school. Healthier lunches were served, for instance, and the sweets in the vending machines were replaced with dried fruits and nuts. Principal Nichols hires "Enslave the Mollusk", a band, to perform a song about the Fitness Zone. However, during the mentioned band's meeting concerning the song, Artur Pashkov, their lead singer, ditched them. Nate developed stage fright and when he opened his mouth, nothing comes out. As a last resort solution, Francis Pope starts singing terribly, rendering the entire concert a failure.
Finally, Fitness Zone initiates Field Day to encourage the students involved. Shortly before the event, Marcus Goode bets that the sixth grade will not win any sport at the occasion. Nate accepts the bet, and if he loses, he will have to briefly join Marcus' posse and gradually act like a Marcus wannabe.
Things are not looking good for Nate's bet, as the sixth grade had not won a single activity. The only sport left is the three-legged race. In an elaborate scheme, Nate was able to allow Chad and Maya be the representatives for the sixth grade against Marcus and Jakob representing the seventh grade. In the end, because of Chad and Maya's good chemistry, they were able to take home the gold for that activity, allowing Nate to win the bet.