Pre-K Gains Fade Fast

Greg Duncan and others in WaPo:
“Why don't boosts in these early foundational skills lead to permanent advantages in the academic trajectories of disadvantaged kids? Our work suggests that much of what children learn in early-childhood intervention programs are skills that kids typically pick up in kindergarten or first grade anyway. Fadeout is really a process of other children catching up — learning their letters, learning to count, learning to control their emotions and impulses.
What holds disadvantaged kids back throughout their schooling is not a failure to master the basics. More fundamental to achievement are hard-to-change characteristics such as intelligence and conscientiousness, as well as persistent environmental factors that are difficult to change with a one-time educational intervention. ...
For lasting effects, we need to focus on skills that wouldn't otherwise develop, do more to change a child's environment and provide ongoing support, especially during sensitive periods of development such as early adolescence. …
Another worthy model for interventions targets not just children but their caregivers, with the idea that improving parent-child interactions can affect the whole course of a child's development [For example, Nurse-Family Partnerships]… 
We need to focus on older children as well. Intensive interventions can help with mastery of advanced skills. A high school program offering a double dose of algebra classes has been shown to boost graduation rates. And students who attend career academies, which restructure large high schools into small learning communities and promote concrete vocational skills, can typically expect higher earnings as adults. Vocational skills, advanced math and literacy skills, and achievement-related beliefs and motivations are examples of what we call "trifecta skills" — skills that are malleable, fundamental to success and unlikely to develop in the absence of an intervention."