In some experimental evaluations of classroom-level interventions it is not practically feasible to randomly assign teachers to experimental conditions. Given such restrictions, researchers may randomly assign students to experimental conditions and consider the teacher to be a part of the intervention. However, in an individually randomized…

Randomized experiments have become an increasingly popular design to evaluate the effectiveness of interventions in education (Spybrook, 2008). Many of the interventions evaluated in education are delivered to groups of students, rather than to individuals. Experiments designed to evaluate programs delivered at the group level often…

The purpose of this study was to determine the effects of the Jigsaw method, a cooperative learning tool, on content knowledge and attitude toward learning science. A group of 64 students in an 8th grade physical science class located in rural western New York participated in this study. As an intervention for this action research study, science…

Background: Multiplication and division by fractions are among the most troublesome concepts in the elementary mathematics curriculum. Recent studies have shown that preservice elementary teachers in the United States do not have deep understandings of these concepts. Effective ways to improve preservice teachers' conceptual understanding of these…

The New York State Experimental Prekindergarten Program (PreK) evaluation studied successive waves of children while they were in PreK, and as they progressed through the third grade. For each wave, two control groups were obtained: (1) A waiting-list control group, children in districts offering PreK programs who were identified as eligible for…