I think I often do things like that. It wouldn't be something like "Today kids, we learn how to craft pretty figures with chestnuts." but rather things I have realized myself and which amazed me.

Once during an excursion with my study course I rambled for two hours about my current ideas what's wrong with our society. I talked to 2 or 3 people, but they simply sat there and listened, that was pretty cool. They even asked some questions and I was glad to answer them. And if it comes to teaching people how to do stuff (like handling computer programs, I used to explain a lot when I was still in school), I helped whenever I could. I was really proud when somebody told me that I could explain it much better than the teacher. I just tried to put myself in the position of the person who doesn't understand how it works. I figured that teachers often explain things from their professional position which isn't necessarily understood by their students.

It is a really satisfying experience to me to explain things and to help somebody with that, or simply show them another way of thinking.