a bit of thought, a bit of Googlefu and a bit of hunting in the attic and between the three I've remembered and found the short story I was thinking of last night.
It's John Varley's 'Beatnik Bayou' and I should warn about SPOILERS once again. (The story has some interesting points so you might want to read it before reading this). It's in The Best SF of the year #10, 1981 edited by Terry Carr.
SPOILER alert
The 'class' in this case is a group of four 13 year olds who've grown up together since the age of 7 at least and who are on the edge of what counts as adulthood in this society on the moon.
However, two of the 13 year olds are actually teachers - one is aged 48, doesn't say the age of the other - who've been put into the bodies of kids aged 7 and been friends with the two pupils since the age of 7. So they've grown up together. The purpose of the 'teachers' is to lead the students into learning experiences. The pupils know the teachers are older and teachers, but accept the system.
"Cathay... was one... fine teacher. He was able to take those old saws about learning by doing, seeing is believing, one-on-one instruction, integration of life experiences - all the conventional wisdom of the educational establishment - and make it work better than any teacher I'd ever seen."
At the age of 13 the main protagonist is about to graduate to another teacher who will be better suited to his growing needs. One of the "13 year old" teachers is about to regress back to 7 to take on his next class. (Complications ensue).
The new teacher points out the protagonist hasn't, until now, been interested in where his education is going. She explains why he should be interested. "Because you're nearly an adult now. My job, if you hire me, will be to ease the transition. When you've made it, you'll know, and you won't need me anymore. This isn't primary phase. Your teacher's job hack then was to work with your mother to teach you the basic ways of getting along with people and society, and to cram your little head with all the skills a seven-year-old can learn. They taught you language, dexterity, reasoning, responsibility, hygiene, and not to go in an airlock without your suit. They took an ego-centred infant and turned him into a moral being. It's a tough job; so little, and you could have been a sociopath."
"Then they handed you to Cathay. You didn't mind. He showed up one day, just another playmate your own age. You were happy and trusting. He guided you very gently, letting your natural curiosity do most of the work. He discovered your creative abilities before you had any inkling of them, and he saw to it that you had interesting things to think about, to react to, to experience."
"But lately you've been a problem for him. Not your fault, nor his, but you no longer want anyone to guide you. You want to do it on your own. You have vague feelings of being manipulated."
and towards the end they have another conversation:
"I won't be teaching you science or skills either. You'll have tutors for that, when you decide just what you want to do."
"Just what *is* it you do, then?"
"You know, I've never been able to find a good way of describing that. I won't be around all the time like Cathay was. You'll come to me when you want to, maybe when you have a problem. I'll be sympathetic and do what I can, but mostly I'll just point out that you have to make all the hard choices. If you've been stupid I'll tell you so, but I won't be surprised or disappointed if you go on being stupid in the same way. You can use me as a role model if you want to, but I don't insist on it. But I promise I'll always tell you things straight, as I see them. I won't try to slip things in painlessly. It's time for pain. Think of Cathay as a professional child. I'm not putting him down. He turned you into a civilized being, and when he got you you were hardly that. It's because of him that you're capable of caring about his situation now, that you have loyalties to feel divided about. And he's good enough at it to know how you'll choose."
That covers the education side.
THere's also an interesting look at a judicial system and virtual worlds for those interested in world building along those lines. And of course, with Varley, sex. Gay, underage, free....
Hope this helps and is of interest. Glad I found the wretched thing as it was worth rereading and going niggle if I hadn't!
cheers
tc