I was sent to a summer camp in the mountains when I was ten years old. I was assigned to sleep in a cabin full of bunks with some other boys of the same age.
There was an adult counselor who slept in the cabin at night. He also had a day job somewhere else so he just came to the camp at night. That may have kept stuff from happening.
I have since heard of all sorts of sexual things happening when boys are together but nothing ever happened at night with the adult counselor present, however one day we started showing each other how we could get an erection. It turned out that I was the only boy with a foreskin. I got my erection my usual way by tugging on the tip of the foreskin. I always had a good overhang to grab on to. I think the other boys were a bit jealous of my foreskin. That was the only incident of a sexual nature at that camp of which I was aware. I imagine that a lot of stuff happened in the other cabins where older boys lived. All I did was to tug on my foreskin a bit after I got in my bunk at night. We were always tired so I went to sleep very quickly.
When I was eleven I started to get spontaneous erections for no reason at all that I could see. They just happened by surprise. My foreskin was still quite narrow at the tip of the overhang, so I still could not retract.
Just before I was twelve, another boy taught me how to masturbate by pulling by foreskin back and forth with my fist, but keeping the foreskin over the head, as I still could not retract. Working my foreskin back and forth with my fist became a daily routine. As I become more skillful at stimulating myself, I started to have dry orgasms as my body still was not producing semen. When I a little over twelve I had my first wet orgasm and several drops of semen emerged from the tip of my foreskin. Every day, I would rush home from school and go into the bathroom to masturbate. Even though I could not retract, I had plenty of fun.
That was the beginning of puberty for me.