During the past half-century, there has been a trend toward increasing the minimum age a child must reach before entering school in the United States. States have accomplished this by moving the school-entry cutoff date earlier in the school year. The evidence presented in this paper shows that...

A continuum of ages exists at school entry due to the use of a single school cutoff date-making the "oldest" children approximately 20 percent older than the "youngest" children. We provide substantial evidence that these initial maturity differences have long-lasting effects on student...