... I'm assuming that you can? They each have their own application procedure, so none are going to know how many others you apply to? Obviously it would be silly not to narrow it down to two or three, but do people ever keep more options open than that?
If this IS the case, then is there normally a lot of switching around on gcse results day? And if running a certain A level course is dependent on numbers, presumably if students bail out on a school at the last minute, courses could get cancelled.
Just trying to understand how scrupulous people usually are with their applications ...