Mathematics / Elementary

Full Report (1 MB) || Educator's Summary (283 KB)|| Educator's Guide (322 KB)

Review Methods

An exhaustive search considered hundreds of published and unpublished articles. It included those that met the following criteria:

• Schools or classrooms using each program had to be compared to randomly assigned or well-matched control groups
• Study duration had to be at least 12 weeks
• Outcome measures had to be assessments of the mathematics being taught in all classes. Almost all are standardized tests or state assessments.
• The review placed particular emphasis on studies in which schools, teachers, or students were assigned at random to experimental or control groups.

Program Ratings Basis

Programs were rated according to the overall strength of the evidence supporting their effects on math achievement. “Effect size” (ES) is the proportion of a standard deviation by which a treatment group exceeds a control group. Large studies are those involving a total of at least 10 classes or 250 students. The categories are as follows:

Strong Evidence of Effectiveness: At least one large or two small randomized studies with median ES= +0.20 or more.

Moderate Evidence of Effectiveness: At least two large or four small studies (randomized and matched) with median ES= +0.20 or more.

Limited Evidence of Effectiveness: At least one qualifying study with a significant positive effect and/or median ES=+0.10 or more.

Insufficient Evidence: Studies show no significant differences

N No Qualifying Studies: No studies met inclusion standards