This seems achievable by the 8th grade.
> In 2017, the United States spent $14,100 per full-time-equivalent (FTE) student on elementary and secondary education, which was 37 percent higher than the average of Organization for Economic Cooperation and Development (OECD) member countries... https://nces.ed.gov/programs/coe/indicator/cmd
Schools are often the safety net for youths with a wide range of problems. While schools are the catch all for such problems, they're more expensive than fixing other issues like fair wages for the parents of the students (e.g. having hischoolers needing to get a job to support the family rather than study for school).
This high price tag is the result of shifting around other issues to the place where they're inefficiently handled.
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The flip side of this is the "schools are often funded by property taxes and areas that are able to collect more taxes are able to spend significantly more per student even if it doesn't result in a better outcome." Many of these areas already have good student outcomes and the money is spent on on... whatever.
Palo Alto spends $24.5k/student ( https://nces.ed.gov/ccd/districtsearch/district_detail.asp?I... ).
Wyoming county schools spends $11.5k ( https://nces.ed.gov/ccd/districtsearch/district_detail.asp?S... ).
When looking at those, compare the breakdown of revenue sources.
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So, I'll say "no, we're not - but it's not the fault of the schools."
Most adults don't seem to be able to do these things well though, so I obviously have a skewed perspective.
I really doubt high school helps with this.
As a plus, school may introduce people to topics that may interest them and then allow them to find their way in life: from playing an instrument, to gymnastics, to computer programming.
Grades are a fixation of the school system and of all those involved, but they don't measure knowledge accurately. Some companies may not hire you if you have low marks or studied in a less than prestigious school/university, but that has not necessarily anything to do with knowledge and is likely to have something to do with class segregation. So there's a point in making them up.
Vandalism being tolerated is instead a very serious issue the school should address.