A growing chorus of doctors and parents is calling for defibrillators to be placed in high schools and elementary schools across Canada.

They say the devices could help save lives in cases where children with undiagnosed heart problems collapse from cardiac arrest.

Doctors say such incidents are not as rare as one might think, and having a defibrillator nearby could save many young lives.

Dorothy and John McEachern lost their son Chase to sudden cardiac arrest.

"He collapsed at school on February 9, 2006. It was in gym class," says Dorothy.

The avid athlete had an underlying heart problem. His heart started beating wildly. By the time he got to hospital, Chase had already incurred severe brain damage. He later died.

"You could say it's rare, but it does happen to children," says his father, John.

Last month, an eight-year-old Toronto-area boy also died at school during phys. ed class, because of cardiac arrest.

Doctors say sudden cardiac death among school kids is largely a hidden problem. There are no firm statistics, but they estimate that about 100 children and teens die each year, because their hearts suddenly stop.

That's why a growing number of doctors say automatic defibrillators, or AED units, should be available in all schools across Canada. The portable units can shock the heart back into a normal rhythm, boosting chances of survival.

Toronto may be leading the way, with 120 defibrillators donated to local high schools by The Mikey Network, a non-profit organization that places the devices in community facilities across Ontario.

"I hope it's the beginning of a change," says Dr. Joel Kirsh of the Hospital for Sick Children. "I'd like to be a little less busy dealing with families who have lost a child at school."

But some question the cost; they can run up to $4,000 per unit.

"We're talking about saving the lives of young people, and teenagers -- children, who have not yet lived their lives. So it's worth every dollar," says Dr. Michael Gollob of the Ottawa Heart Institute

Chase's parents are part of the campaign. "I want to see them in all schools, high schools and universities to protect kids in the school," says John McEachern.

They know if there had been a unit in Chase's school, he might still be alive.

The Mikey Network's donation package is valued at approximately $400,000 and the organization says all the units will be installed in schools by September 2008. The Network is also donating the cost of training of up to eight staff at each location.

With a report from CTV's Avis Favaro and Elizabeth St. Philip