1) Unfortunately, I haven't seen california valley girls

2) I am not sure what you like, but this a classic about girls in high school that I have fond memories off: C. T., Coed Teasers . IIRC, it was very loosely based on the mainstream film Little Darlings , not to be confused with the porn movie called Little Darlin's , with the lovely Kathi Harcourt and Lysa Tatcher. Another one is Co-ed Fever (do you know Tawny Pearl or Teri Dolan?). There is also French Finishing School with Desiree Cousteau. Or Little American Maid , with a young Bunny Bleu and an equally young Nikki Charm.
I am sure I am forgetting some. There is a Shauna Grant flick I have seen but I don't know much about it anymore. The title seems right up your alley though: Private School Girls .

I hope this has been of help to you.

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2. A film that sounds like what you are asking for is Loose Times at Ridley High. It's very similar to Little Girls Blue 1 & 2 (Girls in Blue). Unfortunately, the DVD transfer stinks.

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