A solid understanding of fractions is the cornerstone for acquiring proficiency with rational numbers and paves the way for learning advanced mathematical concepts, such as algebra. Fraction difficulties limit not only students' educational and vocational opportunities but also their ability to solve everyday problems. Students who exit 6th grade…

The gold-standard for evaluating the effect of an educational intervention on student outcomes is running a randomized controlled trial (RCT). However, RCTs may often be small due to logistical considerations, and resulting treatment effect estimates may lack precision. Recent methods improve experimental precision by incorporating information…

The gold-standard for evaluating the effect of an educational intervention on student outcomes is running a randomized controlled trial (RCT). However, RCTs may often be small due to logistical considerations, and resulting treatment effect estimates may lack precision. Recent methods improve experimental precision by incorporating information…

Relevance interventions have shown a great potential to foster motivation and achievement (Lazowski & Hulleman, 2016). Yet, further research is warranted to test how such interventions can be successfully implemented in practice. We conducted a cluster-randomized trial in ninth-grade math classrooms to test the effectiveness of a relevance…

We report the results of a preregistered, cluster randomized controlled trial of a mathematics learning intervention known as interleaved practice. Whereas most mathematics assignments consist of a block of problems devoted to the same skill or concept, an interleaved assignment is arranged so that no 2 consecutive problems require the same…

We report the results of a pre-registered, cluster randomized controlled trial of a mathematics learning intervention known as interleaved practice. Whereas most mathematics assignments consist of a block of problems devoted to the same skill or concept, an interleaved assignment is arranged so that no two consecutive problems require the same…

The purpose of this study was to investigate the effects of an early numeracy intervention delivered by kindergarten teachers to students identified as having mathematics difficulties. A multigroup growth-modeling-with-random-assignment-to-intervention-condition design was employed. Thirty-two teachers were randomly assigned to the treatment or…

Data-based decision making (DBDM) is an important element of educational policy in many countries, as it is assumed that student achievement will improve if teachers worked in a data-based way. However, studies that evaluate rigorously the effects of DBDM on student achievement are scarce. In this study, the effects of an intensive…

The purpose of this closely aligned conceptual replication study was to investigate the efficacy of a Tier 2 kindergarten mathematics intervention. The replication study differed from the initial randomized controlled trial on three important elements: geographical region, timing of the intervention, and instructional context of the…

This paper presents two studies of an intervention designed to help undergraduates comprehend mathematical proofs. The intervention used multimedia resources that presented proofs with audio commentary and visual animations designed to focus attention on logical relationships. In study 1, students studied an e-Proof or a standard written proof and…

The present study investigated the effectiveness of two short relevance interventions (writing a text or evaluating quotations about the utility of mathematics) using a sample of 1,916 students in 82 math classrooms in a cluster randomized controlled experiment. Short-term and sustained effects (6 weeks and 5 months after the intervention) of the…

Chess in Primary Schools is a whole-school approach to teaching primary school children how to play chess. Children take 30 hours of chess lessons delivered by a tutor who is an experienced chess player, and the school is given the option to set up a chess club as a lunchtime or after-school activity. Chess classes are delivered during the school…

The adoption of the Common Core State Standards for Mathematics (CCSSM, 2010) in 46 states has raised the mathematical proficiency bar for U.S. students. The advent of these new standards is at a time when the body of empirical evidence on the negative consequences of early and persistent difficulties in mathematics is clear, compelling, and…

This study used a randomized controlled trial design to investigate the ROOTS curriculum, a 50-lesson kindergarten mathematics intervention. Ten ROOTS-eligible students per classroom (n = 60) were randomly assigned to one of three conditions: a ROOTS five-student group, a ROOTS two-student group, and a no-treatment control group. Two primary…

The present study aims to contribute to the understanding of the effects of music education, in particular music composition as a classroom activity for fifth- and sixth-graders. The intervention (experimental condition) focused on a three-step-model for music composition, based on the Cultural Historical Activity Theory of education, and has been…