Code Lyoko - Season 4 Episode 7
Crash Course

Jeremy decides to teach Odd, Ulrich, and Yumi how to use the Supercomputer in case he or Aelita are unable to, being X.A.N.A.s favorite targets. During the lesson, Jeremy is attacked by one of X.A.N.A.s polymorphic clones, leaving the others to operate the Supercomputer without help. Aelita is at the final audition with the Subdigitals, competing against two other candidates, and thus cannot be contacted. To make matters worse, the clone heads for her after dealing with Jeremy. Using what they learned from Jeremy, the others are able to rescue Aelita and deactivate the tower without his help. Aelita is also chosen as the winner of the audition despite her walking out on them.