As far as I'm aware,a student cannot officially leave school until the last Friday in June. Many schools let their students have time off for study leave, but this is not the same as having legally left.
You can still sit gcse exams after you've left school, but you have to pay. You can sit them at your local college, either day or evening classes, but you must pay a fee.
The end of a school year AFTER the sixteenth birthday of a pupil, thus some will have to stay on another year, if their birth-date is after the end of the summer term that year, won't they? Surely the GCE exams. for that year are over by the end of the summer term?
flaming, I sat my GCSE's when I was 15 as my birthday is not until the very end of july, which was the summer holidays anyway. So, I left school when I was 15, effectively!