Teen fantasy

I remember this movie where there were a bunch of teenagers in a tree house and they had various surreal experiences like fantasies come to life where they become creatures or talk to creatures which were mechanical in some way. This was some kind of a secret for them. I think this was not English but I could be wrong, and it’s probably not well known. Also there was a scene between a teenage boy and girl in their bed experiencing perhaps their first sexual acts. Nothing explicit is shown except the boy undoing the girls bra and then her parents walk in. This was a movie made before 2000.

Got something to say?