The impact of achievement testing on a Spring-Spring vs. a Fall-Spring basis in evaluation of compensatory education programs is examined. The effects of the summer vacation period and crossing test levels were examined. Significant decreases in achievement test scores were found, at all grade levels, between Spring and Fall test administrations.…

Twelve common errors which can invalidate an otherwise sound evaluation are identified, and ways to avoid them are presented. The hazards are: (1) grade-equivalent scores; (2) inappropriate statistical adjustments with nonequivalent control groups; (3) administering norm-referenced tests at inappropriate times of the school year; (4) inappropriate…