Teaching Machines
Thus far we have talked of the computer only as a tool to be studied and not as an aid to learning in itself. In just a few years, however, the “teaching machine” has become familiar in the press and controversial from a number of standpoints, including those of being a “dehumanizer” of the process of teaching and a threat to the apple business!
Actually, the computer has functioned for some time outside the classroom as a teaching machine. Early applications of analog computers as flight simulators were true “teaching machines” although perhaps the act was not as obvious as classroom use of a computer to teach the three R’s. Even today, there are those who insist that such use of the computer by the military or industry offers more potential than an academic teaching machine. Assembly workers have been taught by programmed audiovisual machines such as Hughes Aircraft’s Videosonic trainer, and the government has taught many technicians by computer techniques. A shrewd observer, however, noting that the computer is called stupid, bluntly points out that any untaught student is in the same category, and that perhaps it takes one to teach one.
A strong motivation for looking to the machine as a public teaching tool is the desperation occasioned by the growing shortage of teachers. If the teaching machine could take over even some of the more simple chores of the classroom, early advocates said, it would be worth the effort.
Formal study of machine methods of teaching have a history of forty years or more. In the 20’s, Sydney Pressey designed and built automatic teaching—or more precisely, testing—machines at Ohio State University. These were simply multiple-choice questions so mechanized as to be answered by the push of a button rather than with a pencil mark. A right answer advanced the machine to the next question, while an error required the student to try again. Pressey wisely realized the value in his machines; the student could proceed at his own pace, and his learning was also stimulated by immediate recognition of achievement. To further enforce this learning, some of the teaching machines dispensed candy for a correct answer. Using this criterion, it would seem that brighter students could be recognized by their weight.
Unfortunately, Pressey’s teaching machines did not make a very big splash in the academic world, because of a combination of factors. The machines themselves had limitations in that they did not present material to be learned but were more of the nature of a posteriori testing devices. Too, educators were loath to adopt the mechanized teachers for a variety of reasons, including skepticism, inertia, economics, and others. However, machine scoring of multiple-choice tests marked with special current-conducting pencils became commonplace.
Another researcher, B. F. Skinner, commenced work on a different kind of teaching machine thirty years ago at Harvard. Basically his method consists of giving the subject small bits—not computer “bits,” but the coincidence is interesting—of learning at a time, and reinforcing these bits strongly and immediately. Skinner insists that actual “recall” of information is more important than multiple-choice “recognition,” and he asks for an answer rather than a choice. Called “operant reinforcement,” the technique has been used not only on man, but on apes, monkeys, rats, dogs, and surprisingly, pigeons.
During World War II, Dr. Skinner conducted “Project Pigeon” for the military. In this unusual training program, the feathered students were taught to peck at certain targets in return for which they received food as a reward. This combination of apt pupils and advanced teaching methods produced pigeons who could play ping-pong. This was in the early days of missile guidance, and the pigeons next went into training as a homing system for these new weapons! To make guidance more reliable, not one but three pigeons were to be carried in the nose of the device. Lenses in the missile projected an image before each pigeon, who dutifully pecked at his “target.” If the target was in the center of the cross hairs, the missile would continue on its course; if off to one side, the pecking would actuate corrective maneuvers. As Project “Orcon,” for Organic Control, this work was carried on for some time after the end of the war. Fortunately for the birds, however, more sophisticated, inorganic guidance systems were developed.
The implications of the pigeon studies in time led to a new teaching method for human beings. Shortly after Skinner released a paper on his work in operant reinforcement with the pigeons, many workers in the teaching field began to move in this direction. For several years Skinner and James Holland have been using machines of this type to teach some sections of a course in human behavior to students at Radcliffe and Harvard. Rheem Califone manufactures the DIDAK machine to Skinner’s specifications.
To the reasons advanced by those who see teacher shortages looming, Skinner adds the argument that a machine can often teach better. Too much time, he feels, has been spent on details that are not basic to the problem. Better salaries for teachers, more teachers, and more schools do not in themselves improve the actual teaching. Operant reinforcement, Skinner contends, does get at the root of the problem and, in addition to relieving the teacher of a heavy burden, the teaching machine achieves better results in some phases of teaching. It also solves another problem that plagues the educator today. It is well known that not all of us can learn at the same rate. Since it is economically and culturally impossible except in rare cases to teach children in groups of equal ability, a compromise speed must be established. This is fine for the “average” child, of whom there may actually be none in the classroom; it penalizes the fast student, and the slow student perhaps even more. The teaching machine, its proponents feel, takes care of this difficulty and lets each proceed at his own rate. Since speed in itself is no sure indicator of intelligence, the slow child, left to learn as he can, may reach heights not before dreamed possible for him.
Many educators agree that automated teaching is past due. James D. Finn, Professor of Education at the University of Southern California, deplores the lack of modern technology in teaching. “Technology during the period from 1900 to 1950 only washed lightly on the shores of instruction,” he says. “The cake of custom proved to be too tough and the mass production state, at least 100 years behind industry, was not entered except here and there on little isolated islands.”
These little isolated islands are now getting bigger and closer together. The Air Force has for some time trained technicians at Keesler Field with U.S. Industries AutoTutor machines, and also uses them at the Wright Air Development Center. The Post Office Department has purchased fifty-five U.S. Industries’ Digiflex trainers. Following this lead, public education is beginning to use teaching machines. San Francisco has an electronic computer version that not only teaches, tests, and coaches, but even sounds an alarm if the student tries to “goof off” on any of the problems. The designers of the machine selected a sure-fire intellectual acronym, PLATO, for Programmed Logic for Automatic Teaching Operations. The System Development Corporation, the operations firm that designed the SAGE computer, calls its computer-controlled classroom teacher simply CLASS. This machine uses a Bendix G-15 computer to teach twenty youngsters at a time.
To show the awareness of the publishers of texts and other educational material, firms like Book of Knowledge, Encyclopedia Britannica Films, and TMI Grolier are in the “teaching machine” business, and the McGraw-Hill Book Company and Thompson Ramo Wooldridge, Inc., have teamed to produce computerized teaching machines and the programs for them. Other publishers using “programming” techniques in their books include Harcourt-Brace with its 2600 series (for 2,600 programmed steps the student must negotiate), Prentice-Hall, and D. C. Heath. Entirely new firms like Learning, Incorporated, are now producing “programs” on many subjects for teaching machines.
Subjects available in teaching machine form include algebra, mathematics, trigonometry, slide rule fundamentals, electronics, calculus, analytical geometry, plane geometry, probability theory, electricity, Russian, German, Spanish, Hebrew, spelling, music fundamentals, management science, and even Goren’s bridge for beginners.
While many of these teaching machines are simply textbooks programmed for faster learning, the conversion of such material into computer-handled presentation is merely one of economics. For example, a Doubleday TutorText book costs only a few dollars; an automatic AutoTutor Mark II costs $1,250 because of its complex searching facility that requires several thousand branching responses. However, the AutoTutor is faster and more effective and will operate twenty-four hours a day if necessary. With sufficient demand the machine may be the cheaper in the long run.
The System Development Corporation feels that its general concept of automated group education will be feasible in the near future despite the high cost of advanced electronic digital computers. It cites pilot studies being conducted by the State of California on data-processing for a number of schools through a central facility. Using this same approach, a single central computer could serve several schools with auxiliary lower-priced equipment. Even a moderately large computer used in this way could teach a thousand or more students simultaneously and individually, the Corporation feels. After school hours, the computer can handle administrative tasks.
In the CLASS system developed by the System Development Corporation, the “branching” concept is used. In a typical lesson program, if the student immediately answers that America was discovered by Christopher Columbus, he will be told he is correct and will then be branched to the next item. If he answers Leif Ericson, the computer takes time out to enlighten the pupil on that score. Next, it reinforces the correct date in the student’s mind before asking another question. Although it would seem that a lucky student could progress through the programmed lesson on guesswork alone, the inexorable laws of probability rule this out. He cannot complete the lesson until he has soaked up all the information it is intended to impart. He can do this without an error, in a very short time, or he can learn by the trial-and-error process, whichever is better suited to his speed and mental ability.
Making up the program for the teaching machine is a difficult task and requires the services of technical expert, psychologist, and programmer. An English-like language is used in preparing a CLASS program for the computer. Put on magnetic tape, the program goes into the memory of the computer and is called out by proper responses from the student as he progresses through the lesson.
Complex as the programming is, entries from the student’s control are processed into the computer in about one-tenth of a second, and an answer is flashed back in about the same amount of time. Remember that the CLASS computer is handling twenty students at a time, and that in addition to teaching it is keeping a complete record of how the student fared at each step of the lesson.
It is obvious that the binary or yes-no logic of the computer ties in with the concept put forth by Skinner and others of presenting small bits of information at a time. We can use the game of 20 Questions as a good analogy. Even getting only simple yes-no answers, skilled players can elicit an amazing amount of information in often far less than the permitted number of questions. Thus even complex subjects can be broken down into simple questions answerable by discrete choices from the student.
The automated group education system of the System Development Corporation is made up of the following components: a digital computer to control and select the material presented and to analyze responses, a magnetic tape storage unit, a typewriter for printing out data analysis, a slide projector and screen for presenting educational materials, and individual desks with keyboards for the students’ responses.
We have pointed out that even though it is possible to break down educational material into multiple-choice or yes-no answers to which are assigned intrinsic values, the ideal system permits answers on a linear scale. In other words, instead of picking what he considers the most nearly correct, a student writes his own answer. Some experts feel that the advances being made in optical scanning, or “reading” techniques for computers, will result in linear programming of the teaching machines within the next ten years. Such a development will do much to alleviate the complaint that the machine exerts a rigid mechanizing effect on the teaching process.
While fear of displacement motivates some teachers to distrust the machine, an honest belief that the human touch is necessary in the schoolroom is also a large factor against acceptance. Yet these same wary teachers generally use flash cards, flip charts, and other mechanical aids with no qualms. The electronic computer is a logical extension of audiovisual techniques, and in time the teacher will come to accept it for what it is.
The human teacher will continue to be an indispensable element in education, but he must recognize that as our technology becomes more complex he will need more and more help. In 1960 there were about 44 million students in our classrooms, and about 135,000 too few teachers. By 1965 it is estimated there will be 48 million students and 250,000 teachers fewer than we need. Parallel with this development is the rapidly growing need for college graduates. One large industrial firm which employs 150,000 hires only 300 college graduates a year at present, but will need 7,000 when it automates its plants. The pressure of need thus is forcing our educational system to make use of the most efficient means of educating our students.
Beyond simply taking its place with other aids, however, the computer will make great changes in our basic concepts of teaching, according to Dr. Skinner. He asks the question “Are the students who learn in spite of a confusing presentation of a subject better for the experience, or were they better students at the outset?” He advances this argument to say that perhaps “easy” learning is actually the best; that we would do well to analyze the behavior called thinking and then produce it according to these specifications. The traditional teacher finds the prospect alarming and questions the soundness of minimizing failure and maximizing success.
There is not yet definite agreement by other psychologists with Skinner’s contention that recall rather than recognition is the desired method. Neither is it sure that the negative reinforcement of a number of incorrect choices may result in remembering wrong answers. And of course the division between rote learning and creativity is an important consideration. The answers may well lie in the computer, which when properly programmed is about the most logical device we have available to us. Thus the machine may determine the best teaching methods and then use them to teach us. Regardless of these as yet unanswered questions, however, the future of the teaching machine seems to be assured. One authority has predicted that it will be a $100 million market by 1965.
An intriguing use of computer techniques in teaching is being investigated by Corrigan Communications, which scores students answering questions on telecourses. This work is being done with a course in medicine, and with the rapid growth of educational television the implications of combining it and teaching machine techniques are of great importance.
Classroom teaching is not the only educational application for the teaching machine. A computer-controlled library is an interesting thought, with the patron requesting information from a central computer and having it presented instantaneously on a viewing screen in front of him. Such a system could conceivably have access to a national library hookup, constantly updated with new material. Such a service would also be available for use during school study hall, or by the teacher during class.
Visitors to the World’s Fair in Seattle previewed the computerized information center of the future. Called Library 21, it is considered a prototype of the next century’s core libraries which will be linked to smaller branches by communications networks. Many computers were displayed, tied in with teaching machines, language laboratories, and information from the Great Books, tailored to the individual questioner’s sex, personality, and mental level. Also shown was a photo process that reduces a 400-page book to the size of a postage stamp for storage.
With this kind of progress, we can in the foreseeable future request and receive up-to-date information of any kind of human knowledge anywhere—in language we can understand. Another computer application sure to come is that of handling correspondence courses. The teaching of extension courses in the home, through television and some sort of response link, has been mentioned, and it is not impossible that the school as a physical plant may one day no longer be necessary.
Since the computer itself does not “teach,” but merely acts as a go-between for the man who prepared the lesson or program and the student who learns, it would seem that some of our teachers may become programmers. The System Development Corporation has broken the teaching machine program into three phases: experimenting with the effects of many variables on teaching machine effectiveness, developing a simplified teaching machine, and finally, analyzing the educational system to find where and how the machine fits. Research is still in the first phase, that of experiment. But it is known that some programs produced so far show better results than conventional teaching methods, and also that teaching machines can teach any subject involving factual information. Thus it is evident they will be useful in schools and also in industry and military training programs.