Does the same class get zinged for absences on Fridays? If so, that's a lot of time taken out of the school week for one class. What if it's phys.ed and the gym teacher uses the multi-purpose room/gym? Where do those kids go to have their class? What if the French or drama teacher uses the room (with a stage) for a production? Where do the kids practice?

So maybe the principal now needs to rotate the entire schedule and flip classes so that one class is not badly zinged by these prayers. How does that fit in with half-time teachers who only work part of the day? 

The multipurpose rooms are also used at lunches for groups such as choirs or clubs. Where do those kids practice? The schools in the GTA where Muslims are going are often overcrowded. 

Did you know that the province does not fund music rooms nor French rooms for grades k-8? So why is there funding and space for prayers? 

It's clearly not "just 20 minutes." 

What I'm saying are just practical considerations.