One of the reasons for its success was White's approach to teaching. He emphasized personal vision and style over any particular school or movement. Students were assigned "problems" and asked to create images that evoked particular concepts or sentiments, such as "Innocence" or "Thanksgiving". He also required students to experiment, much like he and Stieglitz, by producing several kinds of prints of the same image. Of the 30 hours of instruction offered each week at the school, 14 were taken up by a single class – "The Art of Photography", taught by White. During these sessions White stressed that the primary thing his students had to learn was "the capacity to see." He never encouraged or permitted competition among his students by comparing the work of one against another; each person's work was approached totally in relation to that person.