It seems to me that the real issue is whether schools should report potentially troublesome behavior of a minor child to her parents. And the answer, clearly, is "Yes."
If a child is doing badly in one of her courses, the parents should be notified before they get the failing grade on a report card, so they can try to straighten it out. If a child vandalizes school property, the parents should be told. If a child misbehaves in any way, the parents should be told. The parents are the proper guardians of a child, and should normally be told about ANY potential problems their child is getting into.
So, why is this different? No, I know, I don't need to ask. Gay relations are a political third rail. Nevertheless, it's quite proper to tell the parents if a child is smooching on school property, with a member of the same or opposite sex. Whether or not it's a legal offense, the parents should know what their children are doing.
The real problem is that liberal judges want to keep parents entirely out of schools, so they cannot enforce their own values on their children. The schools want total control, so they view informing parents about how their children are doing as a violation of privacy. Nonsense. Minor children don't have privacy from parents if they are doing something wrong or questionable. Parents need to know what their children are doing.
This child's name sounds Asian. I would guess that she has strict, traditional parents of the Asian school, but that she is turning into a rebellious American teenager. It's a tough situation, but it isn't the school's job to help her rebel against her parents.