First, I think it is highly untrue, at least in America, that schools here don't say the pledge of allegiance. I've been to elementary schools in Ohio, Virginia, West Virginia, and North Carolina, a middle school in NC, and am now in a high school in Colorado—they all do it. You might be thinking of the moment of silence for 9/11 or some such, since I do recall my first hour had no such event.
Also, can you point us to some specific citings of not being 'allowed' to pray in school? In this heaping pile of crap of a video that so many have disliked, uploaded by Rick Perry, he blatantly states "...but kids aren't allowed to pray in school, or celebrate Christmas". This is BS because no school I've ever heard of 'disallows' Christian beliefs to be expressed. Rather, Perry wants praying to be mandatory from what I can tell, because every government installation that I've seen doesn't restrict the freedom of religion. Heck, its even in our constitution.
So yeah, kids are allowed to pray in school, they just don't have to at this stage.