It was in Canada although I don't imagine that has any bearing on the situation. It was also at a Catholic private school that shared the property with the church. I literally walked like 20 meters from the school building across the parking lot to the church and it typically only took 1 hour or so. In my own memory, people would get out of school for all manner of reasons, from sports to even family vacations, for entire days with no one batting an eye. I find it hard to imagine any school system so strict that a kid couldn't get dispensation for 1 hour of extracurricular activities during the school day.