Both men — who were employed by Securitas, a private security company — have been removed from any school within the Peel school board.
"Our understanding is that the security company has a safety protocol in place and safeguards in place including a criminal record check for all of their officers," said Carla Pereira, spokesperson for the Peel District School Board
The arrests were made on Dec 4, but not revealed until a week later.
The school also conducted its own investigation but no students were suspended
The board put security guards into all of its schools in late November as a precaution, in anticipation of labour action by members of the Ontario Secondary School Teachers' Federation.
The guards perform some of the supervisory work that used to be done by teachers.
Securitas guards are still working in board schools
"Our clear expectation as a board is that this type of situation is not tolerated in our schools and we'll do everything we can to ensure it doesn't happen again," Pereira said.
Kristijan Rados, 20, and Michael Wiszniewski, 19, are both charged with possession for the purpose of trafficking.
Both men will appear in court in January.