There is increasing interest in meta-analysis in different fields due to the need to combine the results of primary research. One of the crucial concepts in combining results is weighting. This study examines how Hunter and Schmidt's method, weighting by sample size; Hedges and Vevea's method, weighting by inverse variance; and Osburn and…

"Jigsaw" is a peer learning procedure derived from social interdependence theory, which suggests that individuals positively linked by a common goal can benefit from positive and promotive social interactions (Aronson & Patnoe, 2011). Although jigsaw has often been presented as an efficient way to promote learning, empirical research…

The purpose of this meta-analysis was to assess the overall effects of automaticity training of fundamental literacy component skills (i.e., letter names/sounds, individual words) on reading fluency and comprehension. Another purpose was to assess if the effects of automaticity training varied for reading fluency and comprehension. We identified…

In this meta-analysis, the authors synthesize results from 44 (quasi-)experimental studies on informational and narrative text structure interventions involving students in grades 4-6 in regular school settings. Findings show that text structure instruction had positive immediate effects on students' reading comprehension but that effect sizes…

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In this meta-analysis, I have reviewed published and unpublished research on single-track, year-round education's effect on science and social studies achievement, 2001-2016.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…

This meta-analysis reviews experimental and quasi-experimental studies in which upper-elementary, intermediate, and secondary students with learning disabilities learned from graphic organizers. Following an exhaustive search for studies meeting specified design criteria, 55 standardized mean effect sizes were extracted from 16 articles involving…

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…

A vertical scale, in principle, provides a common metric across tests with differing difficulties (e.g., spanning multiple grades) so that statements of "absolute" growth can be made. This paper compares 16 states' 2007-2008 effect size growth trends on vertically scaled reading and math assessments across grades 3 to 8. Two patterns…

Even though there numerous books, articles, research studies, and other publications written since National Council of Teacher of Mathematics (NCTM) published "Curriculum and Evaluation Standards of School Mathematics" in 1989 have advocated the use of manipulatives in the teaching of mathematics, there is no conclusive evidence showing that the…

Background: Many countries rely on immigrants for population growth and to maintain a skilled workforce. However, many such immigrants face literacy-related barriers to success in education and in the labour force. Aims: This meta-analysis reviews experimental and quasi-experimental studies to examine strategies for teaching English literacy to…

The authors reviewed all peer-reviewed studies with participants from preschool to Grade 8 for this meta-analysis of morphological interventions. They identified 22 applicable studies. Instructional effects (Cohen's d) were averaged by linguistic outcome categories (morphological sublexical, non-morphological sublexical, lexical, and supralexical)…

This report presents results from a new quantitative synthesis of research on the effectiveness and validity of test accommodations for English language learners (ELLs) taking large-scale assessments. In 2006, the Center on Instruction published a review of the literature on test accommodations for ELLs titled "Practical Guidelines for the…

This article reports a synthesis of intervention studies conducted between 1994 and 2004 with older students (Grades 6-12) with reading difficulties. Interventions addressing decoding, fluency, vocabulary, and comprehension were included if they measured the effects on reading comprehension. Twenty-nine studies were located and synthesized.…