Gambit

Well, you guys helped me with this once before. Now I present a new puzzler.

When I was younger, I caught a film on Cinemax a few times. It appeared to be European, probabaly from the early 80's. From what I can remember, it depicted a teacher (or tutor) who's only two students that I can recall were two young and very attractive girls. They all end up at this summer house, and various indiscretions ensue. Two scenes that stick out in my mind in particular are of the two girls trying to get their teacher to lay out in the sun with them by the pool as they are nude sunbtahing, and another deals with one of the girls mother in a sauna.
I also recall at least one of the girls having piercings on her nipples and other body parts, which was pretty rare to see at it's time.

I know this is pretty tough, but I would be eternally grateful to the person that could help shed some light on what this film may have been. Like I said, it was essentially softcore, with alot of "safe" sex (safe for Skinemax, anyway)

thanks!