When Bepop and Rocksteady put cartoons on the TV, Krang's android suit is shown to have a rectangular vent on its lower back, which disappears seconds later.
When the robbers rob the jewelry store the turtles ditch their disguises inside the restaurant.
The Turtles are basically lambasted by the "On Trail" crowd as being "No good!" after stopping a pair of robbers.
When Clayton Kellerman says "that's a little hard to swallow" Michaelangelo responds in Raphael's voice.