Effectiveness

Findings

The WWC review of interventions for dropout prevention addresses student outcomes in three domains: staying in school, progressing in school, and completing school. The Georgia, Michigan, and New Jersey studies by Dynarski et al. (1998) assessed outcomes in the staying in school and progressing in school domains.

Staying in school. In the Michigan study 2% of accelerated middle school students had dropped out of school two years after entering the program, compared with 9% of control-group students, a statistically significant difference. The Georgia study also found a lower dropout rate among accelerated middle school students—6% compared with 14% in the control group—a difference that was not statistically significant but that is considered substantively important by WWC standards (an effect size greater than 0.25). The New Jersey study found accelerated middle schools had no statistically significant or substantively important effect on dropping out.

Progressing in school. The Georgia, Michigan, and New Jersey studies all found that accelerated middle schools had statistically significant and substantively important effects on progressing in school. In the Georgia study the average number of school years completed at the two-year follow-up was 8.6 for accelerated middle school students and 7.9 for control-group students. In the Michigan study the average number of school years completed at the two-year follow-up was 7.3 for accelerated middle school students and 6.8 for control-group students. The New Jersey study also found higher average years of school completed for accelerated middle school students—7.8 compared with 7.5 for the control group.

Rating of effectiveness

The WWC rates the effects of an intervention in a given outcome domain as positive, potentially positive, mixed, no discernible effects, potentially negative, or negative. The rating of effectiveness takes into account four factors: the quality of the research design, the statistical significance of the findings, the size of the difference between participants in the intervention and the comparison conditions, and the consistency in findings across studies (see the WWC Intervention Rating Scheme).⁶

Absence of conflict of interest

The accelerated middle schools studies summarized in this intervention report were conducted by staff of Mathematica Policy Research, Inc. (MPR). Because the principal investigator for the WWC dropout prevention review is an MPR staff member and was also an author of these studies, they were rated by staff members from ICF International, who also prepared the intervention report. The report was then reviewed by MPR staff members and an external peer reviewer.