Staggeringly Low Productivity
Total k-12 expenditures in this country were about $630 billion two years ago (see Table 25, Digest of Ed Statistics 2008). The efficiency of our education system is less than half what it was in 1971 (i.e., we spend more than twice as much to get the same results "” see Table 181, same source).
So if we'd managed to ensure that education productivity just stagnated, we'd be saving over $300 billion EVERY YEAR. If we'd actually seen productivity improvements in education such as we've seen in other fields, we'd be saving at least that much money and enjoying higher student achievement at the same time.