In my elementary school in the Dark Ages of the 1950's dodgeball was a staple. Common sense, however, prevailed: rather largish balls (like the ones used for 'four square') were used, the smallest maybe 10-12" in diameter and by general agreement of the kids, heads were off-target - hit someone in the head and it didn't count. Nobody wanted to be known as a bad sport who didn't follow the rules we'd all agreed on.
It never ceases to amaze me how many things were handled with common sense and discretion in my youth that now require reams of rules and rigid stupidity.
Aaaah, four square. I remember that. They still played it in the 70's, don't know if they do anymore.