DJ Williams (Columbus Short) is a krump dancer in inner-city Los Angeles. He and his younger brother Duron (Chris Brown) compete in local dance competitions as members of a crew known as the "Goon Squad". Primarily due to one final dynamic step from Duron, the Goon Squad win a cash-prize battle held one night at an underground krumping competition, and the losing home crew responds by ambushing DJ and his crewmates after the show. A fight breaks out, and the leader of the rival group shoots Duron and kills him.
Arrested for assault, DJ is subsequently sent by his mother to live with his aunt Jackie (Valerie Pettiford) and uncle Nate (Harry J. Lennix) in Atlanta, Georgia, where he is to attend historically black Truth University. Nate, the physical plant director at Truth, aims to teach DJ responsibility, and puts the boy to work doing maintenance as part of a work-study program.
While waiting in the line to register for classes, DJ meets a fellow student named April Palmer (Meagan Good), whom he is immediately attracted to. After registration, he moves into his dorm room, where he meets his new roommate Rich Brown (Ne-Yo). Rich takes DJ to a stepping competition on the green between the Truth chapters of rival fraternities Theta Nu Theta and Mu Gamma Xi. The Mu Gamma Xi crew, seven-time national stepping champions, easily steals the show until DJ sees April across the way and runs right through the Gammas' step line in an attempt to speak to her. A fight nearly breaks out between the freshman and the Gamma steppers, whose best stepper Grant (Darrin Henson) is April's boyfriend.
That night, Rich and his friends go out to a local club called the Phoenix and invite DJ along. DJ takes to the dance floor, hoping to impress April and upstage Grant and the Gammas, all of whom are also in attendance. Despite the animosity between DJ and Grant, the Gammas recognize DJ's skills as a dancer, and the Gamma chapter's president Zeke (Laz Alonso) invites DJ to pledge for Mu Gamma Xi. DJ turns down both Zeke's offer as well as an offer from the Theta Nu Theta chapter's leader Sylvester (Brian White).
After learning that April is a student history tutor, DJ signs himself up for tutoring so that he can spend time with her. The two slowly begin a friendship, and DJ takes April out to dinner. During their date, April discusses the importance of black fraternities and sororities with the clueless DJ, and tells him to visit Heritage Hall on the campus' Greek Row. At Heritage Hall the next day, DJ learns about the significant number of African-American historical figures and celebrities who were members of various Greek-letter organizations, and decides to pledge for the Theta chapter along with Rich and their friend Noel (Jermaine Williams). April eventually leaves Grant for DJ, angering her father, Dr. Palmer (Allan Louis), the school's Provost, Gamma brother himself, and an adversary of DJ's uncle Nate because Dr. Palmer once dated aunt Jackie.
After "crossing over" to become official Theta members, DJ, Rich, and Noel join the Thetas' step crew. Dismissing the chapter's traditional step moves as old-fashioned, DJ teaches his frat brothers a few of his old krumping moves. DJ does not notice that, while he is practicing a few of his brother's old dance moves, one of the Gammas is secretly videotaping him so that their crew can learn DJ's steps.
Sly disapproves of DJ's attempts to modernize the Thetas' steps, and challenges DJ to a battle at the Phoenix between his line brothers and DJ's; the new moves against the old. DJ's line brothers lose the competition due to DJ's show-boating, although Sly agrees to let DJ teach the crew some new moves as a compromise.
A few of the Gammas run a background check on DJ, and learn about the fight in which DJ's brother was killed, and for which DJ was convicted for aggravated assault in an unfair trial. This information is forwarded the school's Ethics Committee, which suspended DJ for the remainder of the year, preventing him from stepping at the nationals. Dr. Palmer, who has the authority to overturn the Ethics Committee's decisions, later offers to reinstate DJ, with the provision that he stop seeing April, an offer DJ refuses. When April learns from her father why DJ has been suspended, she questions DJ and learns first-hand the story behind his arrest. DJ's Aunt Jackie, an old girlfriend of Dr. Palmer's, confronts Dr. Palmer and was joined by April who overheard the conversation, leading Dr. Palmer to overturn the Ethics Committee's decision.
DJ, reinstated thanks to his April's help, shows up in time to take part in the final round of the nationals stepping competition, which ends in a tie between the Thetas and the Gammas, and each crew is required to choose a dancer for a head-to-head competition. The Thetas choose DJ and the Gammas, which had secretly recorded DJ's practices, choose Grant, who has learned all of DJ's steps. Going first, Grant does DJ's exact routine from the tape. After Grant finishes, DJ matches Grant move for move, tossing in something the Gammas didn't get on tape: the move Duron performed to win his last competition with the Goon Squad.
The Theta Nu Theta crew is declared the winners of the competition, and DJ is mobbed by his frat brothers as April runs out to kiss him. The scene is captured in a still black and white photo, which is added to the wall at Heritage Hall.
A quote of Martin Luther King appeared just before the credits. "Intelligence plus character. That is the goal of true education."