Professor X believed that study groups enhance student learning. During first class, he encouraged students to contact a Learning Skills Specialist, who would help them form groups, make arrangements for where and when to meet, and supervise the meetings. -Half students did, and met once a week in their respective study groups for duration of course Final exam grade was recorded by TA. Students who met weekly with study groups (Study Group condition) scored two letter grades higher than students who did not meet weekly with study groups (Control condition). Professor X concluded higher scores resulted from study group meetings