What causes the literacy gap and can schools compensate for it? The authors investigated 3 drivers of the gap: preliteracy knowledge, schooling, and the summer vacation. Longitudinal literacy data over 5 time points were collected on 126 five-year-olds attending higher or lower socioeconomic status (SES) schools during their first 15 months of…

Although approximately 5-8% of students have a mathematical learning disability (MLD), researchers have yet to develop a consensus operational definition. To examine how MLD has been identified and what mathematics topics have been explored, the authors conducted a systematic review of 165 studies on MLD published between 1974 and 2013. To move…

The purpose of this analysis was to examine achievement gaps on fractions for very-low-performing students as a function of whether they receive inclusive fraction instruction or specialized fraction intervention and with the shift to Common Core State Standards (CCSS). In three randomized control trials conducted in 3 consecutive years, 203…

The purpose of this analysis was to examine achievement gaps on fractions for very-low-performing students as a function of whether they receive inclusive fraction instruction or specialized fraction intervention and with the shift to Common Core State Standards (CCSS). In three randomized control trials conducted in 3 consecutive years, 203…

The purpose of this set of analyses, conducted on a randomized control trial examining the effects of a fourth-grade fraction intervention, was to assess the initial academic deficit severity hypothesis. With this hypothesis, at-risk students with more severe initial academic deficits are expected to profit less from intervention than do students…

The purpose of this study was to investigate the effects of 1st-grade number knowledge tutoring with contrasting forms of practice. Tutoring occurred 3 times per week for 16 weeks. In each 30-min session, the major emphasis (25 min) was number knowledge; the other 5 min provided practice in 1 of 2 forms. Nonspeeded practice reinforced relations…

This study examined whether there are processing differences between children with Down syndrome (DS; n = 22; 7 years 8 months to 13 years 10 months) and typically developing children (TD; n = 22; 6 years 6 months to 10 years 10 months), matched for receptive vocabulary. The TD children performed better on tests of nonverbal intelligence…

"Evaluation Science Briefs" summarize the findings and implications of a recent study evaluating the effects of an early childhood program or environment. This Brief evaluates the study "Durable Effects of Concentrated Disadvantage on Verbal Ability Among African-American Children" (R. Sampson; R. Sharkey; and S. Raudenbush.)…