EDMONTON -- Two Edmonton public high schools will move to online-only learning after dozens of cases of the coronavirus were confirmed there in the last week.

M.E. LaZerte has 20 confirmed cases of COVID-19, which resulted in about 300 students and 43 staff being asked to quarantine.

The school has about 1,297 students who have been learning in-person.

A parent and her teenage son both believe his class size at the school are a concern. 

"Their class sizes are still really big," Janice Funston told CTV News Edmonton. "And there's really no way to keep teenagers from congregating together." 

J. Percy Page school reported 13 confirmed cases, resulting in about 366 students and 17 staff members being asked to quarantine.

There are about 715 students at that school who have been learning in-person.

Both schools are in the process of contacting all impacted families. They will move to the same model of online learning that was used earlier this year and in December.

Edmonton Public Schools superintendent Darrel Robertson said the division felt it needed a "circuit breaker of sorts" given schools were transitioning into the third quarter and entering new cohorts. 

"It's when we reached that challenging situation where operationally it's difficult for us to continue, that's when we're making the request to transition," he told media on Monday. EPSB had received the greenlight from the education ministry that morning. 

Minister Adriana LaGrange's office told CTV News Edmonton it approved the ask out of an "abundance of caution."

"We consider the operational needs of the school – such as having numerous staff in isolation that makes it hard to continue with a high level of learning for students in school – when making this decision," press secretary Justin Marshall said. 

MORE THAN 90 PER CENT OF SCHOOLS UNAFFECTED: GOVERNMENT

Schools reopened for in-person classes on Jan. 11 after a week of at-home learning following the holidays. 

An organizer of an advocacy group that has been critical of Alberta Education's return-to-school rollout from the start told CTV News Edmonton the lack of funding, physical space and alternative learning models is being felt now. 

"There's too many cases... there's too much of a hazard... and unfortunately, the students are the victims of just not having enough government resources," Wing Li of Support Our Students said. 

The Alberta Teachers' Association, too, wonders too why the Alberta government hasn't yet implemented smaller class sizes to combat transmission. 

"Especially in our high schools where we're seeing 40 kids or 35 kids in those classrooms," Jason Schilling commented. "We should be able to split those classes so there's a greater ability to have social distancing in place." 

Government officials have long maintained decreasing class sizes is not a feasible option. 

However, Robertson says operational challenges posed by COVID-19 cases predated the Christmas break, and even the transition to at-home learning that came before that. 

"I was very grateful that the decision was made to transition all learners from [Grade] 7 to 12 to online learning for that period of time," he told media. 

"Prior to our transition to online learning in late November, early December, I would say that our volume of COVID cases was much greater than it is right now." 

The sentiment was echoed by the government. According to the education ministry, fewer than 10 per cent of Alberta's schools were unaffected by COVID-19. The province's top doctor also said a week earlier that cases amongst school-aged children were declining. Marshall told CTV News Edmonton Alberta was counting about 140 cases per day in this age group in December; the week of Jan. 18, cases numbered just 80. 

Robertson said the school division has been told the majority of cases are coming from outside the school. 

The board says in-person learning is expected to resume on Feb. 8.

St. Joseph High School in Red Deer is also shifting to at-home learning. A letter to parents said the decision was made because 68 per cent of students and 71 per cent of staff are currently in quarantine.