It didn't really cross my mind much. When we wrestled I'd sometimes to a hip toss or something, but for the most part I was just like the rest of the kids. Of course, it wasn't some sort of intense training camp of how to brutalize your enemey, the classes were extremely focused on self defense. My sensei knew that kids needed a chance to use this stuff though, so we usually sparred a little each week. It gave us a chance to practice with people that knew how to fall down instead of looking for bullies on the playground.
I may not be a typical case though. I went to my uncle's dojo, although I never learned from him directly. I'm not sure if it was because our classes didn't mesh up or if he was avoiding a conflict of interests. If I had to wager I'd say the latter.
In any case, my dad knew from years of my uncle's experience that my sensei was good with kids and knew exactly how to teach them. When I go looking for a class for my son I won't have that benefit, so I expect to interview quite a few senseis and then spend some time watching them teach kids before I pick anyone.