Burrhus Frederic “B.F.” Skinner (1904–1990) has been called the most influential psychologist of the 20th century, but the Harvard professor who invented operant conditioning also shaped teaching. Skinner invented the teaching machine, a mechanical device that allowed users to respond to questions and receive rewards for correct responses. In The Technology of Teaching, he outlined five main obstacles to learning (fear of failure, task too big, lack of directions, lack of clear directions, and lack of positive reinforcement) and ways each can be overcome (give immediate feedback, break task into smaller steps, repeat directions as necessary, work from the simple to the complex, and give positive reinforcement).
