ABANDONED. girl with moped/scooter doesn't fit in at fancy school

[Corey]

I read this YA novel around 1990, but I think it was written (and set) in the 80s.
The story is about a teenaged girl (possibly named Angela???) from a working class background who transfers to a fancy high school (I think it was a boarding school but maybe just a prep school).
The main character rides a moped or scooter (red?) and uses it to escape from her stuffy new environment. The book referred to the moped/scooter by its brand name ("her Honda/Yamaha/etc.").
The girl had brown hair; she may have been Hispanic, but I'm not sure about this.

[Brooke]

Could it be Looking for Alibrandi?

[Corey]

Nope. The book I'm looking for was set in the US and was written prior to 1990.

[Lobstergirl, au gratin]

Corey, are you still looking for this book?

[Lobstergirl, au gratin]

No response, moving to Abandoned.