I think this is the one part of UK culture I will never be comfortable with: the premium placed on exam scores. It is appalling to me that a teenager's access to higher education, or a decent apprenticeship, or a well-paying non-minimum wage job, could be cut off based on exam performance alone - which is exactly how it all comes across to foreigners.
Yes, I suppose some high school coursework could be plagarized, but honestly... how many parents are really actually wading in there and writing their children's coursework for them? When most of us have full time jobs demanding our time? When most of us can't remember trigonometry? Usually parents are told that we're not involved enough! How many teachers marking essays haven't thought of whacking a few sentences that are a little too well-written into Google?
I'm probably still missing some details about how high school coursework is done here - a lot of the education system details have been percolating in as necessary. But this discussion just reminds me of a good friend of mine in high school. She was one of the most intelligent, intellectual, and academically capable girls in our grade. She was also one of the most hard-working, and put in way more effort with her classwork than the rest of us. She had one of the best GPAs in our grade and aced her class final exams each year. Her grades and essays won her enough scholarship money to pay for her first year at a selective, private university in the northeastern USA (which she was accepted to on early decision, IIRC - tuition price per year in the tens of thousands of USD - that is how much money people were willing to pay her to go to uni). Following a Bachelor's in Mathematics at this university, she went on to do a Master's in Mathematics for the fun of it, and then finally decided to teach high school mathematics. She is no slouch.
Her SAT exam scores at age 16 were lower than mine. Some people bomb timed exams, no matter how much they try to study or how much they try to relax during test time. Would you really have shut that girl out of your university math programme - a girl who was taking Advanced Placement Calculus at age 17 and getting A grades in the class - based on the exam scores she managed to achieve at age 16? Would you really have made it all about one test?