Never been asked about school records and I doubt they care. All they want to know is did you pass their requirements (whatever they are, all slightly different)
I got kicked out of a few classes here and there, eventually "grew up" and settled down. Got a job (actually several to pay for it all) and did it all part time.
If however, you're going for some scheme (ala CTC, OAA etc) they are extremely competitive and so a "couple of GSCEs" won't cut it.
If I knew then what I know now I would have got extra tuition in maths and physics and studied French.