I am trying to get a list of some of the things people wish they had learned earlier than they did. Like a life lesson, or something that life experience showed you that once you knew, you said, "Why don't they teach this in school?" I would have acted differently had I understood this. It is anything from small things to large life changing things. I am trying to come up with things to make sure I expose my children to, so they have a chance to learn it early in life.
Obviously some things only come from experience and making enough of the same mistakes, but get the experience early enough it may click in faster.
An example of a broad topic here that I wish I had understood sooner, is money, investing and compound interest. How about you?