Continuity mistake: Phoebe is going into the school in one scene, but as the camera moves she vanishes while on screen.
Visible crew/equipment: When Kel gets up to get more water you can see one of the cameras.
What Game Does Blue Want to Learn? - S2-E15
Continuity mistake: When Steve and Blue are in the felt frame playing Tic Tac Toe, the X on his shirt is larger but as he skidoos back home, the X is smaller.
First Kiss - S1-E17
Visible crew/equipment: At the end of the episode when Harvey hops away, a boom mic is visible. (00:21:55)