It's a No-Brainer & The Shore Thing

It's a No-Brainer: Buster beats the Brain at a class Math-a-thon, so the Brain gives up on his studies and Buster must represent the class. Buster realizes that he cannot represent the class and comes up with several plans to turn the Brain back to the way he is.
The Shore Thing: Arthur, Buster, Binky, Sue Ellen, and the Brain are excited that Arthur's dad is going to take them some place better than the waterpark Aqualand. Although disappointed that they are brought to the beach, Arthur's dad tells them about Ocean Zone and leaves them to find it. They have fun at the beach and realize that that is Ocean Zone.