Afraid of the dark? Why Canadian schools are closing for the solar eclipse

As North America prepares for a once-in-a-lifetime solar event, school districts across eastern Canada are weighing potential learning opportunities against possible risks, with most coming down solidly on the side of safety. 

Many school boards are making arrangements to ensure students are not at school during the total solar eclipse on April 8, cancelling classes or opting for early dismissal. They cite concerns that kids might damage their eyes by looking directly at the sun, or that the mid-afternoon darkness will make their trek home dangerous.

The path of totality — an approximately 200-kilometre-wide swath where the moon fully blocks the light of the sun — stretches through cities and towns in Ontario, Quebec, New Brunswick, Nova Scotia, Prince Edward Island and Newfoundland. While the full eclipse will only last from one to three minutes, the event is expected to last for more than two hours during mid or late afternoon. 

In Toronto, which falls just outside the path of totality and will only experience a partial eclipse that will peak at 3:19 p.m. ET, the city's biggest school board rescheduled a professional development day for teachers from April 19 to April 8.

"As the eclipse will occur around the dismissal times of many schools, there were concerns that children would be outside and possibly looking directly at the sun, which without appropriate protection, can lead to serious problems such as partial or complete loss of eyesight," reads a letter to parents, signed by Toronto District School Board director Colleen Russell-Rawlins.

The safety issues aren't to be taken lightly, according to a Toronto ophthalmologist who specializes in retinal diseases.

When a person looks at the sun, it's typically so bright that their eyes will reflexively close from irritation, said Panos Christakis. But during an eclipse, only a fraction of the light comes through, so your eyes can tolerate looking for a longer period, increasing the risk of damage.

It would be painless at the moment, so a person would not realize until it was too late that they had permanently lost a significant amount of central vision, a condition called solar retinopathy.

That puts a heavy burden of responsibility on teachers in a classroom setting, he said.

"It just might be hard if a class is looking at this eclipse, having people monitoring to make sure that kids are not looking around the special glasses or are not using the right protection," Christakis said. 

Eclipse-safe eye protection, such as the ISO 12312-2 glasses, are specifically developed and tested to prevent eye damage during an eclipse. But they're not effective if they're not being worn, he said.

"They're thousands of times darker than regular sunglasses, so really, you can't see anything except an extremely bright light," he said.

"Kids may be underwhelmed by that experience and start peeking around them."

Tracy Webb, an astrophysicist with the Trottier Space Institute at Montreal's McGill University, worries the school closures are depriving kids of a valuable learning experience.