From statistics I've read (like surveys on jackinworld.com), it appears that the number of boys who experience orgasm before puberty is a small minority. But I see that some do, and I'm glad that I am among those who did.
If the statistics I see are right, most boys miss out on a lot of good fun and pleasure before they get to puberty. I certainly didn't. I sure didn't. I was masturbating in first grade, and think I even started earlier. In my early years I mostly rubbed myself on the support poles to swingsets when I climbed them, small trees, anything that I could get my legs around so I could press my crotch against it. I have very fond and happy memories of hanging onto things like that and feeling the warm, pleasant throbbing of an orgasm, the great feeling that radiated from my crotch, and the warm afterglow of serenity that followed and stayed with me as my little penis felt sensitive.
I don't remember how often I did it, but I'm pretty sure I found a chance to do it nearly every day, and some days, like when I wasn't in school, I'd visit my swingset several times a day.
Of course I had no idea what I was doing; all I knew is that it felt good and I looked forward to it. I showed several of my friends how to do it. A couple of them weren't interested; I think they didn't do it right and didn't get the good feeling, and without that why bother? I can remember a couple who really liked it, and would do it with me whenever they were at my house. We'd wait until we thought my mother was out of the house or working in her sewing room, which didn't look out at the back yard, and mount either end of the swingset. My mother must have seen us, though, since we did it so much.
The best was my cousin. He was a year or two older than I was, and when I showed him, he loved it and became a frequent user of my swingset and anything else he could find. We spent the night together a lot, and in good weather we'd sneak out after my mom fell asleep and do it in the dark. When the weather started getting cold, we found alternatives, one of which was our pillows, another of which was each other. We'd strip naked under the covers and take turns rubbing on each other until we had our orgasms. This became our favorite activity, and one I was able to repeat with one or two friends.
Needless to say, none of us had any surprises about orgasms and stuff when we reached puberty. We had been doing it for years.