During the Game Night scene at NYU, Moose and Camille win a round by using the clue about their 5th grade teacher. Camille also says to her friends that they have known each other "for forever". But later in the movie, when Moose and Camille are making up, Moose hears the song from the ice cream truck and says it is the song they met to freshman year at MSA.
In the final dance off where Luke and Natalie are doing their routine Luke changes his hat to face forwards for when he spins Natalie but when she lands it is on backwards again without him touching it.
When Natalie first walks up to Luke when they are about to lose the battle, her hair is in a side ponytail. Then when she goes to do her flip, its suddenly down. And when the crew comes out in their light up outfits her hair is in a side ponytail again.
During the very first dance battle Moose has on his initial visit and tour of NYU, he knocks a street vendors colorful wares of their table onto the ground to make room for his dance move. When the camera changes angles, everything he knocked to the ground is missing.
When Moose arrives at the second battle against Gwai aka the water dance, he rides his bike in and hits a water line, without wearing gloves, yet after running to his crew to start their line he has gloves the rest of the time.
During the final performance Natalie is in a cut off tank during her first appearance. But when the entire crew comes out with the lights suddenly she is in one of the light outfits. Then at the end of the performance she is in her cut off tank again.
The goof items below may give away important plot points.
In the final scene, the Pirates meet up with Natalie in Grand Central Station, where she and Luke are catching a train to California. Taking a train from NY to CA is questionable to begin with, but there aren't any that make that trip from GCT.