Here's the full story from Entertainment Weekly :
EW has learned that Victoria Justice, former star of Victorious, will appear as herself on an installment of Nickelodeon’s boy band sitcom this spring. The episode, titled “Big Time Tour Bus,” is notable for another reason as well — it’ll be directed by band member Carlos Pena, who plays jokester Carlos on the show.
In “Big Time Tour Bus,” the boys find themselves caught in traffic while traveling to their next gig. It’s up to Justice to keep the concert’s audience entertained as the guys try to figure out what to do next.