The Professor invents a new hat that allows him to speed up, stop or slow down objects or people for a science fair. He forbids the girls from taking it out of the house. But Buttercup disobeys and shows it off at the park, where Ace tricks her into betting it in a game of "Horse", but when she loses, she's forced to ask her sisters for help.
- The Bus Came Back: The Gangreen Gang finally return after their last speaking appearance in Tiara Trouble way back in season one, with all others being wordless cameos. Only now they have an episode all to themselves as the central antagonists.
- Cheaters Never Prosper: During Blossom's attempt to win the hat back, the gang help Ace by knocking away the ball or moving the basket which Ace considers fair enough to claim his prizes. The girls almost squash them with the basketball court for this but are stopped by the hat's power. When the Professor challenges them and gets serious in the second match, Ace calls for the others to help him. But the girls tie them up to make sure Ace plays fair this time.
- Hustling the Mark: The Gangreen Gang manage to keep hustling the girls out of some of their belongings. Eventually the Professor gets involved who likewise challenges them. But apparently doesn't know how "Horse" works and likewise loses his initial match. He eventually proposes one last bet in which if he loses again, the girls and he will leave Townsville. Once Ace accepts however, the Professor suddenly rips away his clothing to reveal a basketball outfit underneath and easily schools the gang in the game, showcasing he was setting them up all along.
- Loophole Abuse: When the Professor forbade Buttercup from taking the hat to school. She promises she won't, though she gets around this by taking it to the park instead.
- Lost Him in a Card Game: Buttercup loses the hat in a game of "Horse" and, later, both Blossom and Bubbles loses her favorite trigonometry ruler and pigtails respectively.
- Noodle Incident: Apparently Buttercup got the girls involved in something involving tricycles and pruning shears at one point. Which Blossom, Bubbles and the Professor cite as the most major irresponsible thing she's done.
- Running Gag: After the Gangreen Gang win their first two matches, a picture of a real life horse in glasses comes up sprouting "You Got Horsed!"
- Time Master: Essentially what the hat the Professor made allows of its user. Allowing them to slow down, speed up or stop people or objects via the traffic lights.
- You Are Grounded: The Professor tells Buttercup this after he wins the last game of "Horse" for getting them in the situation in the first place.