More importantly, when feedback is given through the details of the correct answer, students learn more than when they are just told whether their answer is correct or not (effect size: 0.58). Fuchs and Fuchs (1986) conducted a meta-analysis of 21 different reports on the use of the feedback to and by teachers, with frequencies of between 2 and 5 times per week. The mean effect size on achievement between experimental and control groups was 0.70 standard deviations.