Coronavirus has closed Washington’s schools, at least through summer. When will it be safe to return?

A little more than three weeks ago, Washington Gov. Jay Inslee temporarily closed schools to slow the spread of the novel coronavirus. On Monday, he extended the closure through the end of the school year.

But it’s difficult for the more than 1 million students currently at home to know exactly when they’ll return to learning in classrooms with their peers: figuring out when school should resume requires a tricky calculus.