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1.
Gym Teacher-ing is defined as one who wears sweatpants and sweatshirts at inappropriate times (like at a party). This comes from the lackadaisical nature of gym teachers and their ability to hold professions which require them to do nothing and still get paid a salary, so in effect pointing out that some one is "Gym Teaching" (wearing sweatpants & sweat shirt) is an insult.
I was lazy and tired to day, so I Gym teached to classed.

"Yo you ready to go to the party?" friend

"Yeah but your not why the hell are you gym teacher-ing right now?" me
by Regs99 April 28, 2010