I have vivid memories of when I was a Cub / Boy Scout and in a Civil Air Patrol Cadet practicing first aid on the other boys. We would simulate CPR and injuries. I would use my stethoscope to listen to their hearts against their bare chest. I would make sure to press it on their nipples. While we never took out pants off I could always see their patns tenting with boy boners (mine too) and I would masturbate as soon as I could afterwards.