Parents should teach a lot of things, but we can't trust them to, hence standardized curriculum that teaches things that 'everyone should know'.
Sadly, many of the basics are going away, for some ridiculous reason. Kids REALLY should know some things once they graduate:
- How credit works (and why it's dangerous) as well as basic money management (why it's important to save, budgeting, etc)
- How to cook (or eat healthy)
- Why you should never talk to the police without representation
- More time/importance on the constitution and how local/state/federal governments work
- How to drive and the etiquette of the road (you should get a license just because you can fog a mirror). This should cover bicycles as well!
- How to handle/interact people you don't like or agree with
- And much more
Why these kinds of things? Because our society depends on all of them in order to function. Parents are often busy, neglectful/forgetful, or just shouldn't be parents at all (it doesn't exactly take a certification to pump out kids). Kids should have the opportunity to get exposure to these things no matter how good/bad their home education is. Otherwise, that's how you get people camping in the left lane of a 5 lane highway, doing 65, while traffic is going as fast or faster... and thinking everyone ELSE is in the wrong. Obeying the law is all well and good but functionally meshing with society is just as important.