The study is conducted in the Metropolitan-Nashville Public Schools. Teachers decide if they want to participate. Parents of students in their classrooms decide if they want their children to participate in the study; participation means students complete the study's pretesting and posttesting, and teachers report their test scores on a school-collected measure. Students decide if they want to participate. Teachers complete a survey, report student scores on the school-collected measure, and are observed during CFI implementation.
Each CFI session comprises 3 segments. In Segment 1 (10-12 minutes), teachers conduct that day's CFI lesson. In Segment 2 (10-12 minutes), students work in pairs, taking turns being "coach" and "player" as they explain their thinking and solution strategies taught in that day's Segment 1. Students use CFI help cards to provide constructive feedback to each other. Segment 3 (5-7 minutes) is independent practice.
The primary end-points are students' posttest fraction ordering, fraction number line estimate, fraction calculations. Secondary end-points are students' performance on more distal fraction measures. Other measures are a teacher survey describing fractions instruction and reliance on CFI procedures and their perceptions of CFI's effectiveness and feasibility, as well as CFI adherence from audio recordings and live observations of teachers implementing CFI.