Ours are set for maths, English, science and PE.
I know what sets they are/were at secondary because it's come up in conversation with the child or with the teacher-albeit with the science one because they were furious at being in that set because they wanted to be in a lower set and do double rather than triple. 🤣 They definitely loved being in the lower PE sets because they felt it was far more fun.
I do know of a school that went to lengths to keep it secret, which in my friend's case came with a huge shock. She'd thought all along her dc (and dc thought this too) was top set. It came as a shock when they came to GCSE predictions and the teacher predicted C when she'd been expecting an A/A*. The school was very anti telling any sort of level and enquiries tended to be met with "they're doing very well" or "they're at the right level for them". So that wasn't the only issue (nor was it the only subject they had a nasty surprise, but that was the hardest I think).
I did some very basic research about how children felt about setting (in maths), and I came up with something which I didn't expect. I did it with a mixture of interviews and questionnaires.
The lower the set on average the happier they were about setting. They said they felt happier being able to ask questions, and say they didn't understand because they didn't have the top ones saying "I've finished" while they were still struggling with question one. They felt they did better because they had something to aim for rather than feeling they'd never catch up with the top, and they felt less rushed. A number said something like "now I'm with people like me I feel I can do maths".
The top set was generally fairly indifferent (a couple of complaints about not being able to coast!).
I think I only had one child in a lower set who said he really hated setting, and when we talked he said it was because his dad had got upset with him and told him he wasn't trying hard enough, which is a parent issue not a set issue.
Surprised me at the time because I was expecting the top sets to love it and the bottom to hate it.
And actually that reminds me of one of the bottom sets I dealt with. They were a group of about 10, mostly lads who were very disengaged with schooling and if I put it "challenging". One of the lads in the group had Down's Syndrome, and when I was talking to them (I did some in groups) this lad said he liked being in that set because he learnt new things and "would I like to see how he drew a circle".
The other lads stopped what they were doing and said "go on miss" and "he's really good!"
So I asked him to show me and he solemnly got out a 10p coin and drew round it. The whole set erupted in (sincere) whoops and cheers. One of them proudly told me how he'd shown him how to do that, and another showed how he "wasn't as good. Am I, miss?"
I think about that group. They'll be approaching their 40s now, and I hope they have all been successful. It was a very rough area and it will have been very easy for them to have been drawn into the wrong side, but that little episode showed how wonderful they were.