As someone who went to Peel highschool in the 1990s, and as someone who was present at these same Friday prayers 20 years ago (which caused no objections from anyone back then) I can tell you that most of the year, Friday prayers take place either during lunch hour, or after school (depending on the time of the year). There are small periods of the schoolyear where the Friday pryaer time extends into the timing for the 1st-class after lunch, in which case teachers gave 15 minutes for Muslim students to arrive a bit later than everyone else, but they didn't stop any of the lesson or teaching - the Muslim students had to take it upon themselves to stay after school if necessary to cover any material they might have missed in that small 15-minute slice of the entire week. 

Again, as I have repeatedly said, this entire ruckus is much-ado about nothing. I *wish* I could describe it as people making a mountain out of a molehill, but there's no molehill to even begin with.