An awful lot of your formative years are spent at school learning stuff that doesn't really end up helping us in any way. Sure my Asian studies class may have helped me know the capital of Brunei during pub trivia but there were probably some far more important lessons I could have been learning. If we wanted to really enrich people's lives through school and prepare them to live successfully there would be some other things I would teach.
Gambling - why it is stupid.
There are literally billions of dollars wasted on gambling each year in Australia by people who think they have a chance at winning. It gets glorified as some endearing national characteristic but each time I hear some TV commentator say "Australians love a punt" I realise they are really just saying "Australians are idiots".
Mental health - what the hell is going on.
I spent the first 25 years of my life thinking the only people who had issues were the people locked away in the asylum. What's going on inside our heads is pretty fundamental to how we understand and relate to each other. If it is always some dirty little secret you become freaked out by things and totally ill equipped to deal with them.
Girls - ???
Going to a boys school doesn't really help things but even people who went to co-ed schools still often have no idea. Maybe with a few lessons and a bit of straight talking we would be better prepared for all that relationship stuff. Maybe we would all be happier and have a lower divorce rate.
Rebellion - why not to follow the well trodden path. Fit in, do as we say, accept what I'm telling you - we get get the creative streak kicked out of us pretty quickly at school. Critical thinking needs to be encouraged rather than contained. The most successful people are non-conformists. Often the status quo is crap and it takes a rebel to shake things up.
Trampolining in to a big foam pit - I did this once. hey should make it a subject because it is just really fun.