Found effects

The WWC found Everyday Mathematics^® to have potentially positive effects for math achievement for elementary students

Improvement index

The WWC computes an improvement index for each individual finding. In addition, within each outcome domain, the WWC computes an average improvement index for each study and an average improvement index across studies (see WWC Procedures and Standards Handbook, Appendix F). The improvement index represents the difference between the percentile rank of the average student in the intervention condition and the percentile rank of the average student in the comparison condition. Unlike the rating of effectiveness, the improvement index is entirely based on the size of the effect, regardless of the statistical significance of the effect, the study design, or the analysis. The improvement index can take on values between –50 and +50, with positive numbers denoting favorable results for the intervention group.

Based on the one study that meets WWC standards with reservations, the improvement index for math achievement is +12 percentile points.

Summary

The WWC reviewed 72 studies on Everyday Mathematics^® for elementary students. One of these studies meets WWC evidence standards with reservations; the remaining 71 studies do not meet either WWC evidence standards or eligibility screens. Based on this study, the WWC found potentially positive effects in math achievement for elementary students. The conclusions presented in this report may change as new research emerges.