I want to say AP was introduced to NFHS Rules circa 1985-87 because we used it during at least one of my years of CYO basketball.
I still remember how during the first year of the AP arrow, an official told my dad -- who would serve as a substitute timer for the school when nobody else was available -- that AP was changed on
every inbounds pass.
I don't think I've been part of a lower level (MS or CYO) game with more than 22 AP throw-ins (yet). My 8½ x 11 3-part stat forms can handle 22 per sheet and my 8½ x 14 has boxes for 25, and I can't recall using the opposite page to track AP. I'm not sure I'd want to see that many held ball situations though.
