Well, I was a third grade teacher until my second dd was born, so I have a lot of experience with a lot of different 8 year olds.
I agree that this is scary behavior. Many girls at 7-9 are in the early stages of puberty (it's not at all unheard of for 9 yr olds to be getting breasts or to get their periods), so there are more hormones flowing than adults are often comfortable with. But, while girls sometimes have crushes and talk about boys or having boyfriends, third grade relationships usually involve getting another girlfriend to write a note to a boy with such scintillating remarks as: "Do you like Sydney? Check one: yes or no." The really risque ones might sit next to their boyfriends at lunch. So talk about french kissing and such is very disturbing. (Unless, does she know what french kissing is? Does she think it is kissing on the cheeks like the French do?) She also might be exaggerating or lying to feel more grown up or for attention, etc. The vaginosis is worrying. I know that it can be gotten without sexual experience, but isn't it normally associated with sexual activity? Did the pediatrician not make any inquiries about it? The most worrying to me is that while 7-9 yr old girls are starting to have hormones flowing, boys are several years away from that and are not usually interested in girls at all. (Although we did still have a lot of boys and girls who were still just friends in the innocent sense at my school, boys and girls still usually like to play with their own gender at that age.) So I think if she is doing these things that she is saying, that she is likely doing them with boys several years older than she. Dad and mom need to majorly step up the supervision. WTF are they thinking, saying it is "too late" and not wanting to intervene in their (young)CHILD'S life??? 8 is soooo young. Most of them still believe in Santa! I know you have no real control, but they need to allow only supervised internet and phone conversations, and just say no to dances and other community sponsored activities. Again, wtf is the city thinking with that? Sheesh. Get her into sports or gymnastics or music or scouting or academic stuff; keep her busy with family and wholesome childhood activities. Give her lots of attention from her parents. Have her checked out by a psychologist. Call her school and explain the concerns and ask for their thoughts on her actions there; ask them to step up the supervision. Poor kiddo. Sheesh.