Ruby and Marcus get entangled in a sibling battle for personal space during a class on undersea life. When Ruby stops to giggle over a fish which looks just like Earl, Earl gets so mad that he floods the school with giant hungry fish! A lonely only child, Earl also abhors siblings who can't get along, and enjoys plunging them into ""an ocean of space""! Drawing on a home economics lesson about cooking, the kids plunge underwater in a pressure cooker to unclog the drain (and drain out the school). But Marcus and Ruby are so caught up in sibling strife that they threaten to upset the pot's delicate balance. Only when the two siblings agree to respect each other's space and work together can the kids successfully open the drain and flood Earl's boiler room!

Despite her wretched singing voice, Ruby is awarded the lead role in the school musical. When her fame goes straight to her head and her monstrous ego begins to irritate everyone, Earl recognizes a perfect opportunity to agitate the gang even more! Matching Ruby's DNA, he repeatedly clones her and her mammoth ego until the school is running rampant with Ruby's -- each one fighting for the center of attention. Billy and the gang fight hard to remain sane and, with a little help from Marcus, they discover a way to destroy every Ruby. Marcus cranks up the radio frequency on his Mega-mind, causing all of the Rubys -- and Earl's computer -- to short-circuit! Sanity is restored to Flying Rhino Junior High, and the real Ruby realizes that she doesn't have to be the center of attention -- at least not all of the time.

Earl rejects Raticus' wish that they celebrate the Christmas holidays together. Unfortunately for Earl, his own wish of having no Christmas is granted when he's paid a visit by the Phantom Raticus! Using Earl's computer against him, Raticus subjects Earl to a world where holidays don't exist -- because the school day never ends! Earl wakes up to discover that it was only a bad dream, but not before realizing how important it is to be with friends and family during the holidays. Morphing the school into a winter wonderland, Earl and Raticus enjoy Christmas festivities together.

Marcus spends so much time with his latest creation, the ""Pal 9000"" minicomputer, that Billy feels left out. But Billy's not the only one irked by Pal, for Earl sees Pal's prowess as a challenge to his own supercomputer! Earl shows off his techno-might by turning the school into the edu-station of the 23rd century: a facility run by a computer gone berserk! Marcus uses Pal to take over the building's errant computer, but Earl strikes back by infecting Pal with a virus, causing him to attack students with the building's desks, chairs and doors! Billy tries to warn Marcus that Pal is infected, but Marcus, thinking that Billy is just jealous, refuses to listen. Only when Marcus sees his friends under attack does he finally take action, cleansing Pal with an anti-virus program. With the help of Billy and Marcus, Pal travels through cyberspace into Earl's computer and completely destroys it, saving the school!