So many of these amateur erotica stories seem to revolve around high school students. I find these to be, well, creepy. You pretty much have to state outright that the characters are 18+; because most high school students are NOT going to be that old. I also happen to be old enough so that any high school student character could be my grandchild, but let that pass....
It would be far better to have the stories set in a college environment. There it can be safely assumed that the characters are of the right age.
There are some other advantages to setting a story in a college.
In high school, your day is quite strictly regulated. You don't have much free time to flirt or otherwise conduct your "affairs", and it's very likely you'll be spotted if you try to skip a class.
In college, you're assumed to be an adult who can set and keep their own schedule. There's more time between classes, and if you decide to skip one, no one will care. It's up to you to make up the work.
In high school, there are going to be some serious penalties for faculty who have affairs with a student, and not just because the student is likely to be a minor. I doubt you'll find even one teacher or staff member who will be even remotely interested in so much as dating a student, never mind having an affair.
In college, while similar rules are likely to be in place, I suspect they won't count for faculty and staff that you don't have any classes or other regular dealings with.
It's not just the potentially too young characters in high school, there's also the too common "living with your sexy stepmom" (and the hot stepsister, of course) trope that creeps me out.
Want to do something like that in a college milieu? You live off campus, and are renting a room from a hot "cougar" who happens to have an equally hot daughter.....
How about plot drivers?
One game I'm going through right now has the protagonist in danger of flunking out of high school if he can't get his grades up high enough. Switch things to college, and you can have it where if he doesn't maintain a certain overall grade point average, he'll lose his scholarship.
Hey, want to mess around with funny chemicals and weird science? High school labs are NOT the place for that. In college, if you aren't actually working with a faculty member on a research project, you can sign up to be a subject in one yourself!
Let's see some really grown up characters in these stories. You're an adult, right? Write about adults!