Dr. Green was investigating the effect of a compensatory education program in mathematics for first-grade students. This study gave a standardized math achievement test to all first-grade students and...

Dr. Green was investigating the effect of a compensatory education program in mathematics for first-grade students. This study gave a standardized math achievement test to all first-grade students and then placed these students in the compensatory education program and administered the program for the next 6 weeks. At the end of the 6-week period, he again administered the standardized math achievement test to these students. However, the company from which he purchased the standardized math achievement test had developed an updated and revised form, which was supposed to be better, so he used the new form for the posttest and found that the students had significantly increased their math score at posttesting time. Therefore, Dr. Green concluded that the compensatory program was effective in remediating poor math performance.