So?
Teaching these things aren't bad. IMO better to learn and know than to be ignorant of it. Especially having open dialogue with you about it too.
Up to you though, you're the parent.
Btw they always teach sex ed to kids at that age, because it's the start of puberty and in some states (and places) 12 year olds are eligible for marriage.
I remember back in school they taught us about condoms and disease and safe sex, consent etc.
It definitely is important but does also indoctrinate you, but I think that was just Catholic school tbh (God will punish you blah blah)