Back in my GCSE days I went in for a Science retake but wasn't allowed in by the deputy head of science as my name wasn't on the list. After I went to the reception to sort the matter out I burst into tears. Eventually, the deputy allowed me to take the exam but in a 'special' room where only a handful of others were taking the exam. The invigilator, who I recognised from other exams, gave me a hint on the final question when he saw that I hadn't written anything with only a couple of minutes to go.
Now I don't know why he did so, or if he had been told that it was my retake or that I had been crying earlier, but I ended up getting an A on that exam due to his help. And I know that since that time he has become a teacher at that school as I used to see him when I attended Sixth Form.
Another time when I had a controlled coursework for GCSE French writing element, I was basically copying my draft from a piece of paper folded up in my hand. I have a feeling my teacher knew this and was the reason she walked out when I was the only one left for no other obvious reason unless she was bored, to let me finish copying. I think she was one of the deputies of the school.
At the second university that I attended, there were tutors renowned for giving away the exam papers or answers, so much so that former students advised to pick classes of those tutors. It was obvious when we used to see the results of those tutors' students all getting firsts and another tutors not doing nearly as well.
This isn't just second hand, as I had many modules for these tutors. One method used by a renowned tutor was for half the seminar questions to be a copy of those in the exam, with a full compilation of the exam-only ones for those that turn up to an optional revision class a week before the exam, in the form of a mock paper. He didn't give the answers, but told us that all the questions he uses are from a specific examining body's website with just the name changed. Safe to say it wasn't too much of a struggle finding and remembering those answers. This method meant that results were correlated with attendance and the ability to find and remember all the answers, so the spread wasn't as fishy.
However, the usual method was simply leaving the exam paper with the answers on the desk and walking out during the seminar break. One tutor who did this went further and gave an exam question as a seminar task and went through the solution. We knew what he was doing when he shouted at a student for taking a picture, which was not a reaction we'd seen previously as he was usually relaxed about that sort of thing. This tutor was best friends with the first tutor, both being seniors of our department. Both were terrible and never actually put in any effort into teaching students the content. Suffice to say their students would have failed if it wasn't for the tutors helping them cheat. For one module, I chose to go to another tutor's classes as I knew would learn at least something, but friends from the other class did pass around the paper to everyone from my class. Thankfully I didn't fully rely on it because the paper was changed last minute after some other staff found out and I ended up getting grades better than most people I knew. I knew this because friends who were doing it in a 'special' room were shown a memo that told them of the changes directed at the invigilators. Although I would've preferred for tutors not to do this, especially as I was a decent student, I'd be lying if I said I'd do anything different if I could turn back time. When people in authority are like this it's hard to know who to go to as you feel it could jeopardise yourself. Not to mention the snitch culture given my 'friends' were benefiting from it.
Now I don't know if another of the tutors who did this was deliberate in her actions or just naive as she wasn't the worst tutor in the world, but she did do this for multiple modules. I just remembered a third module actually where she flashed the solutions on the revision webinar...
When I was at my first uni, friends of mine were boasting about how their old A-Level tutors used to sell papers...
Edit:
I just remembered the head of science used to alter our coursework. He once told me that I really need to learn how to professionally layout documents. But rather than teaching me, he just edited it all himself, and not just the layout I might add. He claimed it was how all the successful public schools worked. During A levels, his chemistry class got far higher coursework results than the other, so I think he probably did the same thing. I remember in one chem coursework after we conducted the experiment, there was a cheat sheet going around by a member of the other class who came into ours. I decided I was better than that and just put my own answers, but did terribly. Thankfully I decided to drop chemistry after AS and steer away from all that politics.
I'm not sure this was deliberate, but our head of 6th form told us to fill in our UCAS application a way that was contrary to the advice I understood to be correct from researching on TSR at the time. He told us not to put our AS level grades down, and even after I did and tried to explain why, as he was in charge of references and submitting, I couldn't refuse. I don't know for sure on this one, but I think he knew that it would harm pretty much every student declaring AS level grades as at my 6th form especially AS grades were terrible. So he probably explained it away as it being policy to not certify our AS level grades even though they were certified.