This was years and years ago, I think I was about 14 and was around the time my penis had first began to start growing noticeably. I was just under six inches long and a little more than five inches around. I used to measure my penis consistently and I loved to show it off.
I went to a school that went from Kindergarten up to eighth grade and I loved the attention I got when standing far back while using the urinal, but only when I knew for sure I was the biggest person in the restroom. When the elementary kids were in the restroom I also went in and could count on one of them standing at the urinal right next to me. Some would glance over at my penis and others would just plain stare.
Once I was real horny during class and was dismissed to use the restroom. When I got there I was alone, so stood at one of the urinals and started masturbating. Soon after I started, two kids came into the restroom, both I would have guessed were second graders. They both started using the urinals right next to me, one on my left side and one on my right. I continued masturbating, but I was not trying to give them a view, although I was not trying to hide. When they had stopped urinating it became apparent to me that I was being watched.
This wasn't them sneaking a peek at my penis while we were using urinals side by side, this was me standing at a urinal masturbating and them watching with their penises out. None of us said a word to each other. In my mind I was thinking this is so wrong and I should stop, but it was feeling too good and one part of me enjoyed having an audience.
I felt the familiar feeling of orgasm coming on and ejaculated a huge load onto the urinal. I flushed several times to make the semen go down and then I washed my hands in the sink. I heard one of the kids say, 'What was that?'
When I opened the door to the restroom my friend had been sent to check on me, so I told him that I took a shit.
I remember feeling very nervous and ashamed the rest of the day, because I kept thinking what if they tell someone what they had seen. As each day went on and I didn't hear anything, I got less nervous. From that day on, I made sure I didn't have an audience when using the restroom.