The basic problem of American education is poverty.

The kids in affluent districts are doing very well indeed.

We've suffered from well-meaning but overconfident policymakers launching programs that "seem right" without proper field evaluation... that could be the case here, too. Maybe nothing should go national until it's been shown to work for several years (at least one business cycle?) in 25 states. And nothing should be deployed to 25 states unless it's shown good results in 12. And not in 12 until it's been in 6, and not in 6 until it's been in 3, and not in 3 until it's been proven in 1-2. (Binary promotion?)