Go/Get Back to School. An acronym used when someone presents a false statement or ridiculous concept. Can also be used as a response if someone uses an unsatisfactory insult.
Aaron: The first man on the moon was Obama.
Joe: Justin Bieber has a cool fashion sense.
An abbreviation of Going Back To Sleep. It can be used when someone is too lazy to write the complete phrase, usually when someone wakes up due to a message and wants to go back to sleep.
N: I heard school is off because of the snow.
N: Same here.