Pfft, I could top you all (with the possible exeption of Eface) in embarissing stories. I've got some stuff that's way to embarissing to even consider posting here, but just to give you an idea, here's one of the moderately bad ones.
This was in 6th or 7th grade I believe. Back then everyone always played kickball at recess. Now I didn't particularely like kickball, nor was I very good at it. But since it was the only thing really worth doing out there, I usually went along with it. I was always the last to get picked though. That didn't really bother me too much, since I fully accepted the fact I sucked at kickball. Well, it was a little embarrising to have both teams argue over who should be stuck with me... But not as embarissing as what was going to happen.
One day I had decided that I had had enough of being the worst person at kickball in my class. I was going to go out there and give it my all even if it killed me. So when it was my turn to kick the ball, I threw caution to the wind and ran up and kicked it with all the strength I had. I guess I must have had more ability than anyone had suspected because when I kicked that ball it went flying over the playground fence.
Now back then I went to a private school that had uniforms. At the time I was pretty overweight (thankfully I'm not nearly as overweight now) so the uniform pants never did fit me quite right. Anyway, I guess the strain of my incredible kick was too much for them, because at the height of my kick my pants split right down the seam. It took everyone a little while to realize why I wasn't rounding the bases, but once they did... the laughter must've lasted for five minutes staight. To add insult to injury, there was no way for me to get a change of pants before the end of the school, so I had to walk around for the rest of the day with my pants held together by clothes pins.