This report identifies mathematics and science curricula as well as professional development models at the middle and high school levels that are effective based on their success in increasing student achievement. The goal of the study was to provide some choice to districts and schools that wanted guidance in selecting a curriculum and that wished to use effectiveness as a selection criterion. Unexpectedly, most middle and high school mathematics and science curricula did not have studies of student achievement with comparison groups, and it proved especially difficult to find effects in either math or science for subgroups by sex, minority status, and urban status. Findings strongly suggest that science curricula is more effective when it is inquiry-based, although math curricula can be effective when standards- or traditional-based.