As for adolescent talk, I've actually heard dumber excuses from a teaching professional, who bewilderingly worried about DD's mental state if her classmates grew breasts before her.

OK, I just laughed out loud at this! WOW! When this teacher talked to me this morning about "adolescent talk" - she said, "you know some of them might know a little bit about the birds and bees". I let her know that DS knows all about human reproduction actually. He would be happy to clarify things for the other students if they aren't clear about how it works. I gave her a wink of course, but DS would actually be surprised if 5th graders DIDN'T know about reproduction because he's in 2nd grade and knows exactly how it works - the science part of it.

Thanks, Dude for the rest of your feedback. I will be sure to give him extra mental support.