3. Cultural anti-intellectualism in school. When was the last time you heard of a high school holding an awards ceremony for kids with high SAT scores, or a pep rally before a science fair? For many Americans, competition in sports is admirible, but competition and celebration of achievement in academics is elitism.
It's not jsut in school - it's present throughout the entire culture. Intelligence is something to be reviled, while being an "Average Joe" or an athlete are idolized.
We have other issues in school, too, but the anti-intellectual cultural influences are a massive hurdle. Quite literally, many of the kids do not care about school at all. I don't even know what the root cause of this attitude is - we all like to blame parents, but I can say from experience that parental attitude is often insufficient to combat other influences.
School standards differ wildly from state to state, as well. I know that I learned things literally years earlier than my ex-stepdaughters did (I grew up in CT, they grew up in CA).
Efforts to improve our schools have been counterproductive in many cases. The No Child Left Behind Act was an attempt to bring the glory of the Free Market to education, with schools competing for resources and having funding cut if they didn't pass the tests. This led to teaching to the tests, rather than a comprehensive education plan and took valuable time out of the normal curriculum...and then de-funded the schools that arguably needed help the most.