Bill Gates gives an interview to Wired magazine and says:
There's only one metric by which the US is going backward—the amount of education per dollar. That's pretty impressive, because we've doubled the amount we spend over the past 25 years. The actual achievement scores are up a tiny bit. Well, actually it's mostly flat, and that's because we aren't really studying what works and what doesn't, so why should we expect to have improved? As long as classroom experience stays the same, it probably won't educate kids any better than it did 20 years ago.
I'd argue that there are other metrics by which the US is going backward, too. The amount of government debt is rising, and marginal tax rates are rising, and the percentage of people who are working has declined (which is bad if you think work is good, but I suppose not so bad if you are enjoying a relaxing retirement).