Students taught by teachers of science with a higher I/D ratio, according to Flanders scale, will achieve more and retain more information than will students of teachers with a lower I/D ratio. This study tested students in high school chemistry and junior high school general science at the end of a year of study in their respective classes. They were then retested four months later. The teachers were scaled according to their I/D ratio. It was found that the I/D ratio of a teacher could be a guide toward determining the success of students so taught in a particular class.