A common motivation for adding control variables to statistical models is to reduce the potential for spurious findings when analyzing non-experimental data and to thereby allow for more reliable causal inferences. However, as I show here, unless "all" potential confounding factors are included in an analysis (which is unlikely to be…

Students are active in shaping the implementation of any curricular intervention. At Paradise Valley Unified School District (PVUSD), more than 1,500 students in Grades 1 to 6 were recipients of the William & Mary English Language Arts (ELA) curriculum units. In this article, we share students' perceptions related to the following three…

Attrition occurs when members of the initial research sample are not part of the final analysis sample, such as due to missing data or leaving the study. Both the overall sample attrition and the differences in attrition between the groups can affect the statistical equivalence of the sample and create potential for bias. The WWC has given careful…

This report summarizes the complex research literature on quantitative methods for assessing how impacts of educational interventions on instructional practices and student learning differ across students, educators, and schools. It also provides technical guidance about the use and interpretation of these methods. The research topics addressed…

Attrition occurs when members of the initial research sample are not part of the final analysis sample, such as due to missing data or leaving the study. Both the overall sample attrition and the differences in attrition between the groups can affect the statistical equivalence of the sample and create potential for bias. The WWC has given careful…

Learning how to give effective feedback can be a difficult task for teacher leaders. This is especially true for what is called "hard feedback"--that is, feedback that challenges the teacher's practice and therefore may cause some level of professional discomfort. Educators at the University of Pittsburgh's Institute for Learning have…

The Communities In Schools (CIS) Model of Integrated Student Supports aims to reduce dropout rates by providing students with integrated and tiered support services based on their levels of need. The model includes preventive services that are available to all students (Level 1 services) as well as intensive, targeted, and sustained services…

Self-regulated learning (SRL) is a conceptual model that can be used to design and implement individualized learning strategies for students with learning disabilities. Students who self-regulate their learning engage in planning, performance, and self-evaluation during academic tasks. This article highlights one approach for teaching SRL skills…

Education research rarely lends itself to large scale experimental research and true randomization, leaving the researcher to quasi-experimental designs. The problem with quasi-experimental research is that underlying factors may impact group selection and lead to potentially biased results. One way to minimize the impact of non-randomization is…

Understanding life on a molecular level is greatly enhanced when students are given the opportunity to visualize the molecules. Especially understanding DNA structure and function is essential for understanding key concepts of molecular biology such as DNA, central dogma and the manipulation of DNA. Researches have shown that undergraduate…

The purpose of this 4-year efficacy trial, funded by IES under the Mathematics and Science Education topic, is to study the efficacy of a (Tier 1) core kindergarten math curriculum, "Early Learning in Mathematics" (ELM), when implemented under rigorous experimental conditions. In the first year of this study (2008-09), kindergarten…

Experimental designs are distinguished as the best method to respond to questions involving causality. The purpose of the present paper is to explicate the logic of experimental design and why it is so vital to questions that demand causal conclusions. In addition, types of internal and external validity threats are discussed. To emphasize the…

This report responds to the need for information on how to improve adolescent writing skills. The study builds upon previously published "Reading Next" results and highlights key elements essential to improving writing. The study used meta-analysis, allowing researchers to determine the strength and consistency of the effects of different…

Modeling the process by which participants are selected into groups, rather than adjusting for preexisting group differences, provides the basis for several new approaches to the analysis of data from nonrandomized studies. Econometric approaches, the propensity scores approach, and the relative assignment variable approach to the modeling of…

Mathematics and art are often considered opposites in the traditional curriculum. In this project with fourth graders, mathematics and art provided a springboard for using fractions, in particular, the multiplication of fractions, using Chinese kites. The project began with a discussion of, "What does an artist really do in a mathematics…