I was fortunate enough to hear the original call of the woman whose son was blissfully unaware when he was sporting an obvious erection. My teenage son and I were rolling in laughter because you didn't understand the problem.
Then I heard Peter's list of ways to hide an erection which brought back memories. In middle school, way back in the day when kids still dressed nicely for school, the female teachers were always getting on to us boys for not having our shirts tucked in. It always irritated me the female teachers didn't have a clue why we'd pull our shirttails out in the first place. The male teachers never cared!
Seriously, when a teacher would call you up to the chalkboard, and the first thing you did as you were getting out of your seat was to pull your shirttail out and put one hand into your pants pocket, the teacher should have known it wasn't a fashion statement!