Single-subject experimental designs have long been used in special education to evaluate the effectiveness of interventions for exceptional children. However, the design has not been used widely in gifted education. In this article, an overview of the main features of single-subject design is presented, and its potential for application in gifted…

Number relationships, which go far beyond counting skills, refer to the ability to represent a quantity in multiple, flexible ways. It is arguably among the most important mathematics concepts in number and quantity. The current study examined the effectiveness of number relationships instruction in preschool classrooms. Participants included 73…

For this study we examined collaborative assessment in counseling 820 German students who were going abroad and who were exposed to the Test to Measure Intercultural Competence (TMIC). A randomized pretest-posttest control group design was used. The control group did not get any test feedback. The remaining groups received written feedback or…

Commentaries regarding appropriate methods for researching professional development have been a frequent topic in recent issues of "Educational Researcher" as well as other venues. In this article, the authors extend this discussion by observing that randomized trials of specific professional development programs have not enhanced our…

Using exogenous characteristics to identify endogenous subgroups, the approach discussed in this method note creates symmetric subsets within treatment and control groups, allowing the analysis to take advantage of an experimental design. In order to maintain treatment--control symmetry, however, prior work has posited that it is necessary to use…

Number relationships, which go far beyond counting skills, refer to the ability to represent a quantity in multiple, flexible ways. It is arguably among the most important mathematics concepts in number and quantity. The current study examined the effectiveness of number relationships instruction in preschool classrooms. Participants included 73…

This article examines changes in the research design, sample size, and precision between the planning phase and implementation phase of group randomized trials (GRTs) funded by the Institute of Education Sciences. Thirty-eight GRTs funded between 2002 and 2006 were examined. Three studies revealed changes in the experimental design. Ten studies…

This paper includes a nontechnical description of methods for calculating effect sizes in intellectual and developmental disability studies. Different hypothetical studies are used to illustrate how null hypothesis significance testing (NHST) and effect size findings can result in quite different outcomes and therefore conflicting results. Whereas…

Background: In exploring how emergent bilingual learners' prior knowledge from home and play contexts might influence their scientific reasoning, this study drew upon two distinct research traditions: (a) experimental research from the developmental and cognitive psychology tradition, and (b) research on culturally and linguistically diverse…

The continuous change characterizing 21st century society has significant implications for higher education. Educators and business leaders increasingly recognize that education within and preparation for a context of change requires learning environments fostering openness, flexibility, and engagement with other ideas and people. Such…

This article reviews several decades of the author's meta-analytic and experimental research on the conditions under which nonrandomized experiments can approximate the results from randomized experiments (REs). Several studies make clear that we can expect accurate effect estimates from the regression discontinuity design, though its statistical…

Childhood obesity trends have increased dramatically over the past three decade's. The purpose of this quantitative systematic review is to provide an update of the evidence, illustrating the efficacy of childhood obesity treatment, considering whether treatment fidelity has been measured and/or reported and whether this related to the treatment…

This three-volume report describes the "SAM (School Administration Manager) process," an approach that about 700 schools around the nation are using to direct more of principals' time and effort to improve teaching and learning in classrooms. Research has shown that a principal's instructional leadership is second only to teaching among…

This "What Works Clearinghouse Procedures and Standards Handbook (Version 3.0)" provides a detailed description of the standards and procedures of the What Works Clearinghouse (WWC). The remaining chapters of this Handbook are organized to take the reader through the basic steps that the WWC uses to develop a review protocol, identify…

In a pilot study at El Centro College, an urban college in the Dallas County Community College District, students in a new-to-college educational framework class were offered an intervention intended to enhance the academic advising process. The intervention consisted of in-class career services advising, degree selection, degree planning, course…