I wasn't going to bother dignifying this with a response, but I'm going to go out on a limb here and assume you're more hurt than a jerk.

I don't know about this "art and craft" of manipulating boys. It wasn't something I was taught. In fact, I was raised to beleive the opposite, that I must avoid boys who would try to manipulate me.

That said, I know there are girls/women that manipulate the fellas. And guess what, there are plently of boys and men that manipulate girls and women. There are just plenty of people out there manipulating people. Sadly, not everyone is nice.

It seems your son, by your account, found a lady that wasn't so nice. But that's not a blanket indictment on the female gender and to cast it as such is unfair and myopic. it also has nothing to do with school dress codes. Girls in school wishing to dress comfortably for the weather has nothing to do with manipulating boys.