The authors evaluated the effects of P-SELL, a science curricular and professional development intervention for fifth-grade students with a focus on English language learners (ELLs). Using a randomized controlled trial design with 33 treatment and 33 control schools across three school districts in one state, we found significant and meaningfully…

This study examined the effect of schema-based instruction (SBI) on the proportional problem-solving performance of students with mathematics difficulties only (MD) and students with mathematics and reading difficulties (MDRD). Specifically, we examined the responsiveness of 260 seventh grade students identified as MD or MDRD to a 6-week treatment…

In 2009, the National Assessment of Educational Process reported that the average reading score for students in one state was lower than that reported for students from 43 other states. The percentage of students performing at or above the accepted proficiency level in reading was 24% in 2009. School curriculum promotes reading achievement, yet…

The purposes of this study were to investigate the effects of an intervention designed to improve at-risk 4th graders' understanding of fractions and to examine the processes by which effects occurred. The intervention focused more on the measurement interpretation of fractions; the control condition focused more on the part-whole interpretation…

Through a synthesis of test publisher norms and national longitudinal datasets, this study provides new national norms of academic growth in K-12 reading and math that can be used to reinterpret conventional effect sizes in time units. We propose d' a time-indexed effect size metric to estimate how long it would take for an "untreated"…