What is it like being an alumni of a school that’s underfunded or neglected? Even if the school is “good” (as in well funded or private), does the learning environment reflect that? Also, the dark side of American schools (shootings) dampens peace of mind for parents since at any given moment some gun wielding individual can storm in murdering those inside (students, teachers, custodians, etc.)
Growing up in the US, other responders are correct that school systems vary a lot depending on what state/district you live in. Over the course of my K-12 education, I attended 10 different schools across three states because my family moved a lot. There were times where I would switch schools and suddenly be way ahead in some subject and have completely skipped over some other topics. As an example, I never took a course in world history, but ended up having three separate US history courses because the different districts taught those subjects in different grades.
I do take issue with some of the commenters painting all US schools with a broad brush as terrible. There are excellent schools in the US and excellent school systems. As an example, I currently live in Massachusetts, and if you took it as its own country, it would be one of the best school systems in the world. In general, the states that prioritize education and pay teachers well end up with better educational outcomes. It’s not that surprising really, but a huge portion of the country seems to ignore that fact or spend money in less efficient ways.