Most students with reading difficulties struggle to read words. We examined intervention effects for students with "significant" word reading difficulties (SWRD; standard score of 80 on at least one pretest measure of word reading), which includes individuals with or at risk for dyslexia. We investigated: (a) What are the effects of…

In this meta-analysis, I have reviewed published and unpublished research on single-track, year-round education's effect on science and social studies achievement, 2001-2016. Of 30 studies that met inclusion criteria and had data from which an effect size estimate could be calculated, 7 reported science outcomes (18 effect size estimates) or…

Randomized experiments are often considered the strongest designs to study the impact of educational interventions. Perhaps the most prevalent class of designs used in large scale education experiments is the cluster randomized design in which entire schools are assigned to treatments. In cluster randomized trials (CRTs) that assign schools to…

In this study, differential item functioning (DIF) trends were examined for English language learners (ELLs) versus non-ELL students in third and tenth grades on a large-scale reading assessment. To facilitate the analyses, a meta-analytic DIF technique was employed. The results revealed that items requiring knowledge of words and phrases in…

To determine whether formative writing assessments that are directly tied to everyday classroom teaching and learning enhance students' writing performance, we conducted a meta-analysis of true and quasi-experiments conducted with students in grades 1 to 8. We found that feedback to students about writing from adults, peers, self, and computers…

Worldwide, the interest of policy-makers in participating in studies from the International Association for the Evaluation of Educational Achievement (IEA), such as Trends in International Mathematics and Science Study (TIMSS) has been growing rapidly over the past two decades. These studies offer the opportunity to relate the teaching and…