(since I actually started school with the people born before rather than after me, and then skipped a grade, I never was  actually the oldest in my class, halas. I was the too young kids the girls laughed at.)

It's clear being older or younger can have a huge effect ; at the time of learning  how to read, some kids have lived 20 % longer, probably spoken 40 % longer ; and the effect of being labelled, very early, a "smart child" or "a failure" can have huge effects in the way-too-normalised system of early education... Especially since teachers talk among them, and entering the next grade kids already ave a reputation...

Un roi sans divertissement est un homme plein de misères