Tutrang Nguyen

Fadeout in an early mathematics intervention: Constraining content or preexisting differences?

A robust finding across research on early childhood educational interventions is that the treatment effect diminishes over time, with children not receiving the intervention eventually catching up to children who did. One popular explanation for fadeout of early mathematics interventions is that elementary school teachers may not teach the kind of advanced content that children are prepared for after receiving the intervention, so lower-achieving children in the control groups of early mathematics interventions catch up to the higher-achieving children in the treatment groups. An alternative explanation is that persistent individual differences in childrens long-term mathematical development result more from relatively stable preexisting differences in their skills and environments than from the direct effects of previous knowledge on later knowledge. We tested these 2 hypotheses using data from an effective preschool mathematics intervention previously known to show a diminishing treatment effect over time. We compared the intervention group to a matched subset of the control group with a similar mean and variance of scores at the end of treatment. We then tested the relative contributions of factors that similarly constrain learning in children from treatment and control groups with the same level of posttreatment achievement and preexisting differences between these 2 groups to the fadeout of the treatment effect over time. We found approximately 72% of the fadeout effect to be attributable to preexisting differences between children in treatment and control groups with the same level of achievement at posttest. These differences were fully statistically attenuated by childrens prior academic achievement. (PsycINFO Database Record

Differential effects of the classroom on African American and non-African American’s mathematics achievement.

We examined whether African American students differentially responded to dimensions of the observed classroom-learning environment compared with non–African American students. Further, we examined whether these dimensions of the classroom mediated treatment effects of a preschool mathematics intervention targeted at students from low-income families. Three observed dimensions of the classroom (teacher expectations and developmental appropriateness; teacher confidence and enthusiasm; and support for mathematical discourse) were evaluated in a sample of 1,238 preschool students in 101 classrooms. Using multigroup multilevel mediation where African American students were compared with non–African American students, we found that teachers in the intervention condition had higher ratings on the observed dimensions of the classroom compared with teachers in the control condition. Further, ratings on teacher expectations and developmental appropriateness had larger associations with the achievement of African American students than for non–African Americans. Findings suggest that students within the same classroom may react differently to that learning environment and that classroom learning environments could be structured in ways that are beneficial for students who need the most support.

Are Content-Specific Curricula Differentially Effective in Head Start or State Prekindergarten Classrooms?

Head Start and state prekindergarten (pre-K) programs can boost the school readiness of low-income children through the use of effective preschool curricula. Encouraging results from some studies suggest that children who receive targeted or content-specific curricular supplements (e.g., literacy or math) during preschool show moderate to large improvements in that targeted content domain, but recent research also suggests differences in children’s school readiness among different preschool program settings. We examine whether children in Head Start or public pre-K classrooms differentially benefit from the use of randomly assigned classroom curricula targeting specific academic domains. Our results indicate that children in both Head Start and public pre-K classrooms benefit from targeted, content-specific curricula. Future research is needed to examine the specific mechanisms and classroom processes through which curricula help improve children’s outcomes.