Art teacher Mark Tufford at the R.H. King Academy in Scarborough shared these photos of the raccoon, later named "King" by students.
Tufford told the Toronto Star he always opens the classroom window when he gets in, and King must have used that as his chance to get inside.
“I looked up and saw the critter standing in the middle of the table, looking right at me,” Tufford told the newspaper.