Religion.
… ok, when did I grow a sister? 
I don’t know, but I’ll trade the crazy one in for you. 
Everything I learned about the bird/bees as a child, I learned from HBO & Cinemax. Seriously.
The whole standing up for yourself, self esteem thing. I ran away from home at 16, it wasn’t for years that I even started to come to terms with the dark side of my childhood. I can cook, clean, budget, do minor repairs, think for myself, research - I’m pretty good at many of the things posters didn’t learn at home and yet … come conflict I’ll cry or run or both.
Our parents taught us little or nothing about money or how to handle it. To be fair, I think their only understanding of money was how to work hard and earn money, spend what you had to and don’t go into debt. Neither of them ever had credit cards, and both died with money in the bank, so there is that. When I was 16, I had to fill out the FAFSA by myself, apply as an early admission to the nearby state university, gather all my documents and register all by myself. My mom had no clue how to do all that and was overwhelmed by a divorce at the time.
My mom didn’t really teach me to cook either, though I did eventually pick up some cooking techniques from her. she didn’t like others cluttering up her kitchen.
We didn’t hear much about sex except some confusing story about milk and cows. What I learned about relationships was in the realm of bad examples, from both parents.
According to my mother, self-esteem is not for children, even when they are grown up. If she ever sensed anyone’s self-esteem approaching normal, healthy levels she would find a way to slash you down to size.
Am I the only one finding this a hard question to answer?
There were a lot of things they didn’t teach me formally. Like, I don’t remember getting a lesson in finance, as far as savings, budgeting, and investment go. I didn’t get an allowance, though. So there wasn’t any material to work with. However, when I started college my mother took me to the bank to open up a bank account, and she taught me how to balance a checkbook. Does that count?
I don’t remember a formal “the birds and the bees” conversation, but my mother once asked if I knew the difference between making love and being in love. I don’t remember the context behind this question, nor do I remember my response. But I can’t blame my mother for not having a real “talk” because I gave her no reason to. I’m sure she was relieved.
One thing I know I wasn’t taught was manners, beyond “thank you” and “you’re welcome”. “Respect” in that house meant keeping your mouth shut. So I don’t remember saying much. When you don’t speak often, it’s hard to put your foot in your mouth and be corrected. Most of the mannerly customs I’ve learned–like bringing a gift when invited to someone’s home or waiting till everyone has been served before eating–has been picked up in adulthood.
Another thing: my parents failed at teaching me how to give my opinion. Or rather, teaching me that is alright to have one! They never asked us kids what we would like, and if we gave our opinion about something, we were promptly yelled at. So to this day, when people ask me how I feel about something, I struggle with what to say. It’s like I’ve learned that simply expressing an opinion is a bad thing to do. And when I’m around opinionated people, I hear myself mentally yelling at them like my father used to.