Not naming your GC on Facebook is very wise. I do not put their photos there either. So far my GSons have not talked about intimate matters with me, but it would be no problem. I would tell their parents they had asked/spoken about it, and I would ask the boys to talk to mum and dad. As a previous teacher who taught all this to 10 and 11 year olds, I'm lucky to have a bit of a head start. Never under-estimate the high emotions that go with relationships and the worry about what others think of me at this age. I always tell boys about periods, in a separate group from the girls, but tell the girls in their separate group that I will be teaching the boys this. I emphasise to the boys that for the girls the onset isn't much fun usually, and not to tease or not embarrass them with questions but to be kind and remember it might give them tummy ache or headaches even. I found the boys to be amazingly kind and compassionate about this.