I was bullied nonstop from about 1st through 10th grade, and it got especially worse after 4th grade. Merciless harassment, teasing, taunting, and even physical assaults and borderline sexual assaults. The verbal stuff was the most constant, but the physical stuff was traumatic.
(Edit-- I had some second-thoughts and went back and deleted specific descriptions of some incidents... in retrospect I now feel like they were a little too personal and a little too graphic for a public post. I wasn't comfortable leaving it as it was--end of edit).
I won't even go into the humiliations of phys ed class. There, the teachers even encouraged it. I still hate P.E.
Why did they do this to me? Because I was an easy and powerless target. I was shy, timid, awkward, skinny, and weak. They could always get a "funny" reaction out of me, because I was easily embarrassed. I was good entertainment. And I never fought back, and I never told. :sigh
You know, a lot of this stuff I haven't thought about in years, even decades. Some of it, I've actually never told anyone. I just put it away in a box and moved on. But I think it definitely contributed to alot of the issues I have now, including my social anxiety and my depression.
The best I can do is to do whatever I can to prevent my son from being bullied (or becoming a bully) when he enters school.