In Education Week by Stanford professor Deborah Stipek:
“Is fade-out inevitable? No. Studies have shown definitively that investment in preschool can yield sustained effects and significant social and economic returns. But fade-out is common and remains a persistent reminder that simply providing preschool to low-income children is not sufficient to achieve long-term benefits.
If we want to sustain the effects of preschool, we need to look at what happens after children enter school. Clearly, the quality of schooling they receive in the early elementary grades matters. Poor instruction can undo the effects of high-quality preschool experiences. But instruction has to be more than good to sustain preschool effects; it has to build strategically on the gains made in preschool.”
“The Preschool Fade-Out Effect Is Not Inevitable”
And see these two summaries by the New America Foundation:
What “Transforming the Workforce” Says About the Importance of Continuity