That's an excellent post, but I think perhaps the major reason American education seems to struggle is that our system is too decentralized. Too much input at the local level often means that the task of educating students takes a back seat to being politically correct for the local school system. And yes, that's a direct slap in the face for all those pinheads who deny evolution, or man's role in climate change. Believe what you want, but keep your religion out of the classroom. We've failed to do this in Texas (along with inadequately funding our schools from K-12 right through college) and so we have a school system currently ranked 49th in the nation. That's in spite of being the second most populous state in the U.S. and currently having the 14th largest economy in the world. While you're at it look at the effect the Texas Textbook Committee has on textbook selection nationwide.
When you look at the education systems that really work in developed nations, they are run at the national level, students are actively encouraged to compete (along with the promise of better jobs), and there are often more vocational programs for academically challenged, but still capable students. In the U.S., it's become obligatory that everyone graduate High School even if they read at a second grade level and are a millstone around the necks of their classmates. In most countries, these guys are just kicked to the curb. If your grades suck, you just aren't advanced to higher grade levels and no resources are wasted on you.