Your sex education was a long time ago. At 8 they do teach kids sex education and how babies are made.
When there is a change in social policy such as homosexual marriage, this will eventually filter through to the schools and sex education.
Just the other day a child said to the mother after sex education. quote; "Mum I know you have done it at least once because you have had me. I know, Mrs. Smith , has done it three times because they have 3 kids". That funny but its a little mature for an 8yr old.
It will be unavoidable when homosexual marriage is legal to prevent it from filtering through to sex education.
I don't think sex education is appropriate at a young age, whether it be heterosexual or homosexual
We just teach our kids that about privacy and that works well.