I have a friend who used to work as an IT worker in a school and part of his job each year was to remove certain pupils from the register and then re-enter them after exams so that their results wouldn't count.
He told me that he'd spoken to other IT workers about it and it's common, he told me that the other method some schools use was to pay £3000 (not sure who to) to expel a pupil whose results were likely to sabotage their league table standings.
Can someone clarify this? And can someone tell me how you know for certain that the results you're looking at are reliable?