This is a SpongeKid SlightPants: Lunch Hour episode.
The lunch lady makes a rule that 'no-one talks in line'. But when someone breaks the rule she never lets them speak AT ALL. Well, at least until Patrick coaxes her to let them speak.
Lunch Lady: (over PA system) Attention, students. No one may talk in line.
(shows kid, SpongeBob, and Patrick walking in line as Lunch Lady drops slop on the kid's plate)
Kid: Hey, what the heck is this?
Lunch Lady: THAT'S IT! NO TALKING EVER AGAIN!
(30 min. later, showing the classroom turning into a madhouse secretly talking)
Patrick: I say we go to the Lunch Lady and scream in her ears!
All Kids: YEAH!
Lunch Lady: I heard that! Go back to your classes! Talk whenever you want, just leave me alone!