the first clue i got was around 6th grade. we were having a sleepover and for some reason decided to play strip poker. i lost pretty quickly and when i took my underwear off, the other guys eyes just went wide. they wound up pulling theirs out as well to compare and i was vastly bigger. of course, i'd also hit puberty at a rather young age so just figured i was more developed than they were as opposed to necessarily "bigger." but there seemed to be a running motif through middle school...some kind of party, hanging out, playing games (not much strip poker after that, mostly truth or dare type stuff), in the course of the game my dick would come out and the other guys would just get really quiet and seem impressed or make some comment about how big it was. though, again, i just kind of figured puberty hadn't fully kicked in for some of them and everyone would eventually catch up, lol.
then, i think it was between 9th and 10th grade, i was talking with my best friend, who was a girl, about measuring and penis size and she asked me if i ever had and what my "stats" were. so i told her and her jaw kind of dropped. so, yes, a girl's opinion in high school definitely gave me more of a clue than a bunch of guys in middle school.
i was never embarrassed to change in front of other guys...but it never really came up much. the only time before college where i had any occasion to change in front of other guys was 6th grade, and like i said i didn't really have much of a clue at that point that i was bigger than anyone else and no one else was really stripping all the way down in gym class, so i didn't either. though i did have one incident where another kid started pointing and laughing when i was in my briefs. everyone turned and looked and he asked, "do you have a boner?" i looked down and didn't, so said "no." his face went a little pale and everyone wound up laughing at him instead. i suppose that experience was one of my first clues too, lol. but since then, i've never felt embarrassed getting changed or naked in front of other guys.
as for getting noticeably hard in public...i was always able to conceal it pretty well in school. i wore my shirts untucked and always managed to be able to move it up into my waistband. the only times i can recall any instance of being noticed at that age were both around 7th grade. one, i was sitting across from this really cute girl in my Spanish class. she was wearing a skirt that day and i could see up it from that angle to her panties. it got me pretty hard, but since i was behind the desk i figured no one could notice...i suppose i should have realized that if i could see under her desk, she could see under mine and i caught her glimpsing and blushing a little. i was nervous for a bit, but she didn't point or laugh or anything, so i figured everything was okay and just tried to focus on getting it to go down before the end of class. then in another class, we were watching a movie and i decided to lay on the floor on my front...i guess i started day dreaming and got a little hard, going down my pant leg. i didn't really think anything of it since it was dark and i turned over on to my back and was laying like that for a few minutes before i looked over and noticed one of the girls in class staring very intently at my bulge. she noticed that i saw her and looked up at me and smiled. any other times i got hard in public, either no one else noticed or i didn't notice them noticing. lol
