Dewey is asked to take an IQ test by his counselor. Fearing that the IQ test is the same test that got him placed with the Krelboyne class, Malcolm plans to sabotage Dewey's test. Trying to convince Dewey to throw the test and failing, he enlists Reese's help. However, his poor test taking skills lands Dewey in the emotionally disturbed Buseys class, rather than keep him in the normal education. Feeling guilty for it, Malcolm tries to convince the counselor to retest Dewey. Despite being sympathetic to his plight, she tells Malcolm she can't do anything about it and he'll have to wait until then. This makes him worried because if Lois finds out about him and Reese sabotaging Dewey, they'll suffer a lengthy grounding. Meanwhile, Hal is recruited by Craig to be his partner playing Jump Jump Dance (a parody of Dance Dance Revolution) at a restaurant arcade. Reese tries to figure out what kind of genius he is. In the end after taking over the class from the teacher, Dewey tells Lois about Malcolm's actions, which not only gets him grounded but also Reese because he's the one who took the test.
Malcolm coaches Dewey on how to "throw" an IQ test so he will not end up in the Krelboyne class. He mentions his concerns because of his own experiences. Malcolm also mentions to Dewey that being in the Krelboynes will make him a target to potential bullies. When he refuses and announces his intent to join the Krelboyne class, Malcolm is desperate to put a stop to it. He memorizes the test enough to give the answers(half of it right and other half wrong) on a paper. Malcolm enlists Reese to take the test for Dewey, hoping to keep him in the normal class. However, his poor test taking skills lands Dewey in the emotionally disturbed "Busey" class instead of keeping him in the regular class. This ends up angering Malcolm for Reese's stupidity.
Malcolm feels guilty for the whole thing and tries to get Dewey out of the class. At Dewey's school, he speaks to the school counselor, Mrs. Welsh, and tries to convince her to retest his younger brother. Malcolm tells her that Lois is a recovering addict who had a "relapse" the morning of Dewey's test. He claims this is due to her anger over finding out about Reese's latest infraction in breaking the law with an unknown and destructive prank he committed. He claims it was both the relapse and their brother's arrest that accounted for Dewey being stressed out enough to scoring the way he did. He also insists that Mrs. Welsh doesn't contact Lois about the matter. When she asks about the reasons against it, Malcolm claims that she's already furious with Reese enough because he broke the law by committing a serious felony and that Hal is trying to calm her down. He also mentions that having her talk about Dewey's poor scoring that lead to him being in the remedial class would make things worse at home and Lois will be stressed out even further to continue drug use. While sympathetic to his plight, she informs Malcolm that she can't do anything but assures Malcolm that she will only communicate with his father from now on. This makes Malcolm worried because if Lois finds out that he and Reese sabotaged Dewey's test, they'll face a lengthy grounding.
Meanwhile, Reese tries to figure out what type of genius he is. After failing at several attempts (including "Hypnotist", "Archbishop", "Dictator for Life", "Skyscraper Repairman", "twin", "fireproof" and "talks to animals") Reese moves on to the next items on his list of potential genius vocations. Lois reminds him not to bother figuring out what genius vocation he is because he's neither book and street smart. She tells Reese that he's an idiot for even attempting this.
After Dewey teaches Hanson why the sound of an approaching motorcycle sounds different than the sound of a retreating motorcycle (the Doppler effect), Dewey realizes that his classmates aren't disturbed as much as they are starved for stimulation. Mr. Sheridan hasn't done anything to teach the class because he's too wrapped up in his own miserable life. Dewey then leads the class out of the classroom and to a takeover of the Krelboyne class whereupon the Buseys seize musical instruments, books and other supplies and return to their classroom to actually start learning. Realizing that he had lost control, Mr. Sheridan concedes defeat and quits his job as a teacher. Because of his actions in taking over the class from the incompetent teacher, Dewey becomes the Buseys leader.
Hal and Craig enter a Dance Dance Revolution-style contest. When Craig suffers an injury, Hal tries to turn to Lois, but ends up getting the help of a kid who knows his and Craig's routine. He only agrees to help him if he get the prize (two free pizzas) and Hal agrees
The next day, Dewey confesses to Lois about Malcolm's plot that got him sent to the Busey class. She is angry, but he claims that Reese was involved too. Malcolm claimed that they didn't want Dewey in the Krelboyne class out of fear that he would be bullied by both her and the kids at his school. Hence, he and Reese plotted to try and keep him out of that class and stay with the normal kids by trying to teach him to throw the test. When Dewey refused, Malcolm ended up enlisting Reese to take the test for him and that's how Dewey unintentionally ended up in that class. He rushes in to excitedly tell Dewey that he's finally figured out what kind of genius he is. Reese proceeds to punch Dewey on the top of the head, knocking him to the floor. "There it was, just staring me in the face... C'mon Dewey, please stay awake. I've got so much to show you!" Reese tells Dewey, implying that his genius superpower is bullying. However, Lois appears and immediately sours his mood by reminding him that he's a delinquent and an idiot. She tells Reese that she now knows his involvement in sabotaging Dewey's test. The episode ends with her grounding not only Malcolm, but also Reese because he's the one who took the test for Dewey.
- Jane Kaczmerek as Lois
- Bryan Cranston as Hal
- Christopher Kennedy Masterson as Francis
- Justin Berfield as Reese
- Erik Per Sullivan as Dewey
- Frankie Muniz as Malcolm
- James and Lukas Rodriguez as Jamie
- Cameron Monaghan as Chad
- Danny McCarthy as Hanson
- Amy Bruckner as Zoe
- Trisha O'Kelley as Mrs. Welsh
- Craig Lamarr Traylor as Stevie
- David Anthony Higgins as Craig
- Kenneth Mars as Otto
- Matt Malloy as Mr. Sheridan
- Amy Castle as Hayley
- Dennis Bendersky as Davey
- David Trice as a manager
- Ayla Kell as Kylie
- David Cox as Special kid 1
- Raven Goodwin as Special Kid #2
- Nikki Lee as Special Kid #3
- Christopher Gerse as Brett
- Louan Gideon as a woman
- First appearances of Mrs. Welsh, David Hanson, Zoe Desenea, and Chad.
- Much like how the gifted class has the nickname "The Krelboynes", this episode shows that the school also has an emotionally disturbed class called "The Buseys".
- Jump Jump Dance Party is a parody on Dance Dance Revolution.
- The songs that play on Jump Jump Dance party throughout the episode are Milkshake by Kelis, The Hampsterdance, a remake of Double Dutch Bus originally by Frankie Smith, a remix of All Around the World by Cooler Kids, and a remake of Sometimes When We Touch originally by Dan Hill.
- Lois called Hal and Craig "Fred and Ginger". This was a reference to Fred Astaire and Ginger Rogers. Two famous dance partners that were featured in many movies about them.
- After being called "Fred and Ginger", Craig said "I thought they were Fred and Barney", referring to Fred Flintstone and Barney Rubble from The Flintstones.
- Bryan Cranston (Hal) said in an interview that he and Dave Higgins (Craig), had to practice playing six weeks of "Jump Jump Dance Party" in order to prepare for their roles in this episode.
- Bryan Cranston's dancing sequence received an Emmy award nomination for "Outstanding Choreography".
- Mr. Sheridan makes his first and only appearance as the incompetent teacher of the Busey class. He is later replaced in season 6 by Mr. Flerch.