The suspended students and their parents had to appear before the discipline subcommittee of the board of trustees.
Mrs Biggs said she tells parents in no uncertain terms that using the drug will not make their children smarter.
"Marijuana use reduces a student's ability to learn. Research has been piling up, demonstrating clearly that the drug limits their capacity to absorb and retain information.
"Regular use can lead to mental health issues in later adolescence."
Mrs Biggs promised to continue to take a firm stand against using drugs at school. Encouraging literacy was the only way to turn out dazzling kids, she said.
"It's all about education, and our children are at school to be inspired ... and our job is just that ... to inspire our students, each and every one of them."