Back-in-the-second-grade

An all-encompassing word/phrase which is mainly used to describe something that took place in second grade of elementary school typically with some chums. Also rarely used with a severely negative connotation and can even be derogatory when used against a small person or a dog to describe male genitalia.

Boy fine dine doe #1: yo remember when we flipped off our rabid a** teacher and Shem back flipped off the meatloaf in homeroom?

Boy slick nasty wit it #2: yooooo!! That was totally back-in-the-second-grade!!!!

Boy fine dine doe #2: OMG OMG LOML I’m such a lumpy weeeeeeen! That was definitely back-in-the-second-grade!