The gold standard in making causal inference on program effects is a randomized trial. Most randomization designs in education randomize classrooms or schools rather than individual students. Such "clustered randomization" designs have one principal drawback: They tend to have limited statistical power or precision. This study aims to…

The present study examines the effect of the cooperative Jigsaw II method on improving literal and higher order reading comprehension in English as a foreign language (EFL). Forty-eight ( n = 48) students of EFL participated in the study and a pretest-posttest control group experimental design was employed. The results indicated no statistically…

This report summarizes the findings from a national evaluation of mentoring programs funded under the U.S. Department of Education's Student Mentoring Program. The impact evaluation used an experimental design in which students were randomly assigned to a treatment or control group. Thirty-two purposively selected School Mentoring Programs and…

A meta-analysis of 29 separate studies investigating pretest effects was conducted. Outcomes of the studies (achievement gains or attitude improvements) were computed as standardized differences between pretested and non-pretested groups. Eleven other variables were coded for each outcome. Initial descriptive statistics were indicative of…