So I mailed out books today and as she was scanning the DC's she tells me that one of the books was to thin. That I could not send it with the PBS postage and DC because it did not meet parcel standards. So She then tells me it must be at least 3/4 of an inch thick. Has anyone else had this issue?

I've heard the rule before. I don't usually have books that thin so it doesn't come up.

Yup if it is too thin it has to go first class and first class doesn't have DC available.

You can get DC on First Class mail, it just has to be 3/4 of an inch thick.

You can get around this by making sure the package is stiff (insert some cardboard) or plumping it up with something that doesn't weigh much like a packing peanut.

Thats a great idea Melanie, I will keep that in mind for the future. It was a childrens book and Ive never sent any books that small. I normally have large heavy books. So when it happened I was just standing there like a deer in the head lights. Of course she was making such a seen about it, I had people looking at me like I was trying to blow up the PO. I just wanted to mail my books lol, oh well I learned something new.

You can use FC or Media with DC but it is supposed to be 3/4" thick. You could also use bubble wrap to make it thicker.

You can also send an extra book to make the package larger.  I am doing that with a WL book I am mailing.  I don this every once in a while just for no reason.          

I used a bubble mailer when I had one that thin to mail and it went out just fine.

I always send my thin paperbacks first class anyhow ... it's cheaper.

I just recently had this problem, too.  No big deal, I just wish I had remembered the 3/4 in. regulation before I sealed the envelope.  Even the postal work said next time to just put a piece of cardboard in the envelope.