Single-case designs are a class of research designs for evaluating intervention effects on individual cases. The designs are widely applied in certain fields, including special education, school psychology, clinical psychology, social work, and applied behavior analysis. The multiple baseline design (MBD) is the most frequently used single-case…

Experimental and quasi-experimental designs play a central role in estimating cause-effect relationships in education, psychology, and many other fields of the social and behavioral sciences. This paper presents and discusses the causal graphs of experimental and quasi-experimental designs. For quasi-experimental designs the authors demonstrate…

Years of developmental psychology research links traumatic experiences to long-term student externalizing problems (Bingenheimer et al. 2005; Denese & McEwen, 2012; Osofsky 1999; Pynoos et al. 1987; Raver, Blair & Willoughby, 2013; Shonkoff et al., 2012). A related body of work relates negative life outcomes with exposure to high-poverty,…

Ratio and proportional relationships, along with the interrelated topics of fractions, decimals, and percent provide a critical foundation for algebra (National Mathematics Advisory Panel, 2008). Solving even simple proportion problems is challenging for many children and adolescents. A small number of studies have examined the efficacy of…

In the last three decades, there has been a large increase in the number of rigorous experimental and quasi-experimental evaluations of education programs in developing countries. These impact evaluations have taken place all over the globe, including a large number in Sub-Saharan Africa (SSA). The fact that the developing world is socially and…

Single-case designs (SCDs) are a class of research methods for evaluating intervention effects by taking repeated measurements of an outcome over time on a single case, both before and after the deliberate introduction of a treatment. SCDs are used heavily in fields such as special education, school psychology, social work, and applied behavior…

Students often memorize and apply procedures to solve mathematics problems without understanding why these procedures work. In turn, students demonstrate limited ability to transfer strategies to new problem types. Math curriculum reform standards underscore the importance of procedural flexibility and transfer, emphasizing that students need to…

The successful acquisition and development of mathematics skills and concepts is a critical aspect of children's early academic growth. The purpose of this study was to systematically evaluate the unique relations of working memory and language to a range of specific early mathematics skills in a sample of preschool and kindergarten age children.…

Policy research on children is heavily balkanized by discipline. Economists bring strong experimental and quasi-experimental methods to their policy research, and recognize in their conception of causation that policies may have heterogeneous treatment impacts. But economic theories make few concrete predictions regarding either the nature of that…

The regression discontinuity (RD) design (Thistlewaite & Campbell, 1960; Cook, 2008) provides a framework to identify and estimate causal effects from a non-randomized design. Each subject of a RD design is assigned to the treatment (versus assignment to a non-treatment) whenever her/his observed value of the assignment variable equals or…

Child and adolescent mental health disorders are known to increase the risk for numerous poor school and life outcomes for children and adolescents including suicidal ideation and attempts, academic underachievement and school dropout, substance use and disorders, and physical fighting or victimization by a weapon (Bradley, Doolittle, &…

Identifying the causal mechanisms is becoming more essential in social and medical sciences. In the presence of treatment non-compliance, the Intent-To-Treated effect (hereafter, ITT effect) is identified as long as the treatment is randomized (Angrist et al., 1996). However, the mediated portion of effect is not identified without additional…

This paper describes a cluster-randomized trial of an after-school program intended to build mathematical identity among students in groups under-represented in science, technology, engineering and mathematics (STEM). Populations under-represented in STEM include women, persons with disabilities, African Americans, and Latino/as (NSF, 2011). U.S.…

Nearly one in five Americans does not graduate from high school (U.S. Department of Education, 2017) and risk of dropout disproportionally affects economically disadvantaged, racial/ethnic minorities. Dropout occurs for many reasons but usually results from cumulative disengagement with school (Fine, 1991; Orfield et al., 2004). Identity-Based…

Peer learning is often used in classrooms to help and support knowledge and skill acquisition. One form of peer learning, peer assessment, involves the quantitative (i.e., peer ratings) or qualitative (i.e., peer feedback) evaluation of a learner's performance by another learner among students. While we might be concerned about the quality of the…