Sixth grade has been pretty disaster-free for aspiring astronaut Maple McNutt--which is impressive, given the number of worries and possible catastrophes that run through her head every day. (So far, Earth hasn't been devoured by a black hole and a cockroach hasn't crawled out of her toothpaste mid-squeeze. Phew!) But then her best friend of seven-point-two years, Sunny Gwon, accuses her of being unfun and starts hanging around with a new group of friends.

In order to win Sunny back, Maple decides to undergo a serious scientific transformation to become fun by 1. Doing extensive research, 2. Applying research to self, and and 3. Repeating until fun. It's risky and groundbreaking research, but Maple has no choice if she wants to save her friendship.