Science Achievement Gaps Begin Very Early, Persist, and Are Largely Explained by Modifiable Factors.

We examined the age of onset, over-time dynamics, and mechanisms underlying science achievement gaps in U.S. elementary and middle schools. To do so, we estimated multilevel growth models that included as predictors children’s own general knowledge, reading and mathematics achievement, behavioral self-regulation, sociodemographics, other child- and family-level characteristics (e.g., parenting quality), and school-level characteristics (e.g., racial, ethnic, and economic composition; school academic climate). Analyses of a longitudinal sample of 7,757 children indicated large gaps in general knowledge already evident at kindergarten entry. Kindergarten general knowledge was the strongest predictor of first-grade general knowledge, which in turn was the strongest predictor of children’s science achievement from third to eighth grade. Large science achievement gaps were evident when science achievement measures first became available in third grade. These gaps persisted until at least the end of eighth grad...