From Mainframes to the Web: 1998 George C. Pimentel Award

Chemical Education Today

Award Address

From Mainframes to the Web

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1998 George C. Pimentel Award, sponsored by Union Carbide Corporation Stanley G. Smith Department of Chemistry, University of Illinois, Urbana, IL 61801

When mainframe computers became widely available in the early 1960s, it was clear that they had great potential in education (1). Computers were exceedingly patient, and tutorial programs written by one person could be used by many students, more than that person could possibly interact with on an individual basis. Studies addressed the question of how computers could be used and what was effective at promoting student learning (2). But there were cost and technological issues to consider. Since the 1960s, there have been many changes in the available technology. The cost of a mainframe capable of supporting an educational network was millions of dollars in the 1960s, which meant that not every institution could have access to lessons developed for those systems. Today, a much more powerful network of computers costs only thousands of dollars. Access to instructional computer programs has become nearly universal. In addition, the screen resolution and the ease with which graphic images can be displayed has increased. Over a thirty-year period much has been learned about how computers should be used to teach and to help students learn. Although computers can display content, a computer is not a book (3). However, computers can be used to engage students in a dialogue that leads to development of concepts needed to learn chemistry. The dialogue can be enhanced by laboratory simulations where students can discover principles by observation, data collection, and analysis. Computers can be programmed to provide guidance to students who may be having difficulty. They can also be programmed to provide immediate feedback to students’ responses. What level of feedback is sufficient and how much guidance students need have been learned by observing students using the material. Students must also feel that what they do on the computer is an integral part of the course. This means that students should be required to work on lessons on the computer throughout the course and that there should be a way of tracking what the students have done. Today the major challenge is keeping up with the changes in technology. The time required to develop instructional material for an entire course tends to be longer than the lifetime of the system used in the authoring process. It is difficult to develop new approaches when one is rewriting existing lessons every two to three years so that they will be compatible with new browsers and operating systems. This

paper will illustrate some of the changes in computer technology that have taken place in the last 30 years and their impact on the teaching of chemistry. MainFrames

Possibilities in the 1960s In the 1960s, computer technology (4) had advanced to the state that it was possible to develop highly interactive instructional computing programs on mainframe computers. However, only terminals connected to the mainframe participated in the network. To write instructional material on the PLATO III computer (4) at the University of Illinois, for example, it was necessary to go to where the machine was located. There were no terminals in remote locations for creating software. This resulted in a community of users in a variety of disciplines interacting with each other to exchange ideas and techniques for the use of computers in teaching. As a result, a very rich and intellectually stimulating environment was created. That kind of environment is difficult to recreate today, since networked computers allow each person to work in the privacy of his or her own office. Because everyone worked together in one room, faculty who were creating “courseware” could provide input to the programmers developing the mainframe’s

Figure 1. PLATO III Workstation, 1968.

Figure 2. Spelling markup made sure reagent names were correctly spelled.

Presented at the 215th ACS National Meeting, Dallas, Texas, April 1998. W

The full version of this article appears in JCE Online at http://jchemed.chem.wisc.edu/Journal/Issues/1998/Sep/ abs1080.html.

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Journal of Chemical Education • Vol. 75 No. 9 September 1998 • JChemEd.chem.wisc.edu


operating system. This meant that when faculty needed a feature to create quality courseware, they could discuss the issue with the people responsible for programming that feature into the computer. The screens were small, and the graphics, by current standards, were poor. Since it was difficult to develop dazzling displays, the instructional design was what held students’ attention. Students were asked to type their responses to questions (5) such as: What reagent would you use to convert 2-butanol to 2-chlorobutane? Response to a student’s answer from the mainframe computer was nearly instantaneous and included the ability to check spelling and comment on specific wrong answers. Figure 2 shows spell-checking when a student misspelled thionyl chloride. Because of the large amount (for the 1960s) of processing power available, it was also possible in the late 1960s to have students identify unknowns by asking the mainframe computer quesFigure 3. Students type the reagents required in each step of the synthesis of 3-pentanone. tions about the properties of their unknown compounds (5). They could request the results from tests that could provide additional information about the Because there are many ways to synthesize a compound, the identity of their compound. The students were expected to computer was programmed to carry out the reactions sugtype their questions which the computer would then answer. gested by the students rather than to compare the student’s Asking the student to formulate questions requires a deeper work to a preconceived list of possible answers. Students level of knowledge than selecting an option from a list with started by typing the name or formula of the starting matea mouse as is often done now. However it does require betrial and then the formula of the reagent for each step in the ter typing skills. The ability to develop this type of instrucsynthesis. The computer would respond by drawing the structional program was the direct result of having systems proture of the product of the reaction and comparing the prodgrammers in the room where courseware was being designed. uct with the structure of the target molecule. The instrucSpecial system software was written just to make it possible tional design that required the computer to draw the prodto engage students in this type of dialog about an unknown uct rather than having the student draw the structure was compound. based on limitations of the system at that time. It was more In 1969, students in an organic chemistry class were difficult to generate a student interface that made it easy to given simple compounds to synthesize on the computer (6). construct two-dimensional formulas than to write a computer program to generate the structure and draw it on the screen. The sequence in Figure 3 illustrates how students could identify starting materials and reagents required to synthesize 3pentanone.

Figure 4. PLATO IV (1972) student terminal with 512 × 512 resolution and touch-sensitive display.

Figure 5. PLATO IV Lesson (1972) on Fractional Distillation with graphics.

Possibilities in the 1970s In the 1970s, computers got bigger, faster, and had better graphics (7 ). Networking made it possible for both developers and students to work at locations other than next to the computer. The network made it more convenient for the users but put a strain on the exchange of ideas between developers. Figure 4 shows the kinds of graphics that could be incorporated into lessons in the 1970s on the PLATO IV system. The PLATO IV system with 512 × 512 resolution, fullscreen graphics, and a touch-sensitive display made it possible to develop complex instructional lessons. For example, before students went into their organic chemistry lab, they were expected to practice performing a fractional distillation on the computer. The software monitored the heating rates and the collection of fractions. The quality of the separation depended on the skill of the student in maintaining column equilibrium and collecting fractions at the right place.

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Did Tutorials Enhance Learning? Because of the interactions and the use of learning strategies within the programs, computer-based instruction tends to be more efficient than other forms of instruction (2). To obtain further information on the efficacy of tutorials, an experiment was devised in which the computer controlled the direction of instruction, and the students were active participants (8). Two sets of prelab instructional programs were prepared. One set required the student to interact with the program by answering questions that demonstrated understanding of the material. The other type of program allowed the students to step through the identical material by simply pressing a key. Both sets of lessons contained animation, simulation, modeling, and text presentation. After completion of the prelab lessons, students went to the lab to perform the experiments. Observers posted in the lab recorded errors that students made in doing the experiments. An example of an activity that requires only following directions is assembling a titration apparatus and performing a titration, following detailed, printed instructions. For that type of activity in which students simply followed simple instructions, there was little difference between groups that had the interactive versions and those that had the passive version of the prelab instruction. However, in sessions where the student had to make decisions requiring an understanding of principles behind the experiment, students following the interactive approach showed significantly better performance. The type of activity that requires an understanding of the principles is using an old-style analytical balance to accurately find the mass of a substance. These data indicate the importance of making instructional material that rapidly responds to the student. The table below represents the results from over 700 students in 30 sections for two semesters at the University of Illinois. A Whole-Course Management Environment This type of instructional computing environment made it possible to write material for whole courses. Online management systems were developed that included a grade book for recording scores and lessons completed. Programs were developed to allow faculty members to choose and order lessons and topics. Online quizzes were graded by PLATO programs and recorded in the grade book. Notes in the form of e-mail could be sent between faculty, among students, and between faculty and students. PLATO also recorded the number of questions each student was asked, the number that he or she answered correctly on the first try, the number of errors made that were specifically anticipated by the author, the number of unanticipated errors, the number of times that students asked for help, and the time spent on each lesson. Using those data, it was possible to revise a lesson if the error rate was too high or to add feedback and additional problems in places where there were unanticipated errors (9).

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Avner (20) studied times to develop instructional material and reported that one group of 22 new authors averaged about 295 hours to produce 1 hour of instructional material, while a group of 8 authors who were proficient in the use of the authoring language required an average of 26 hours per hour of instructional material produced. The instructional environment outlined above changed what we could teach and how we could teach it. But the cost was too high for widespread use. The introduction of the microcomputer changed the cost associated with the delivery of instruction using computers. Microcomputers Microcomputers (10), such as the Apple II, provided processing power similar to one student’s share of a mainframe. Since processing was local, graphics could be faster than was possible from many networked mainframe computers in use at that time. Displaying graphics on networked terminals attached to a mainframe was slow because networks had low bandwidth and because processing power was shared with many simultaneous students in order to control cost. The first microcomputers used for instruction were standalone machines. The instructional software was loaded onto floppy disks and distributed, one set for each machine. To write interactive, instructional material on these computers required a programming environment that made it relatively easy to •

erase the screen

• • • •

display text with subscripts and numbers draw lines, figures, and graphs do calculations accept user input

• • •

judge responses erase selected screen areas store data

Today we would add the ability to display images and play video and audio to this list. Although the BASIC language available on these machines allowed the development of routines that made these functions possible, the efficient writing of a large body of instructional material was facilitated by the development of specialized authoring tools. This simple example shows how answer-judging commands added to Applesoft BASIC could be used to help judge student input: 100&A=" "

In this case, the instructs the computer to convert the student input to lower case so that the answer is not casesensitive. The directive supplies a list of words that can be ignored in the answer, while the directive lists synonyms, one of which must be present in the answer. Students’ answers could be analyzed to the nearest letter, and typical proofreading markup could be put on the screen (11, 12). This represented a significant improvement over the typical “no, try again” for an answer that was not perfect. These tools allowed the developers to focus on the instructional part of the program.



Figure 6. Spelling markup and answer-judging on the Apple II.

Figure 7. Last step in the synthesis of m-dibromobenzene. Apple II program, 1981.

In another type of instructional program for the Apple II, students are given compounds to synthesize. They proceed by selecting reagents, by number, from the boxes at the bottom of the screen. The computer determines the product for each step and draws the structure on the screen. Early microcomputers provided a relatively low-cost way of delivering interactive, instructional material to students. But because they were not usually networked, they lacked an easy way to automatically record a student’s work. The fact that scores and records of completion could not be easily stored in a central location limited the way such material could be incorporated as a required part of the instructional process. Analog Video The development of the IBM PC XT made it relatively easy to superimpose full-motion video (13, 14) on interactive, instructional material that used answer-judging of the type that had been developed on the PLATO mainframe or the Apple II microcomputer. The microprocessor used in an IBM XT microcomputer ran at speeds of 4.7 MHz, and the machine contained 256 kB of RAM. In spite of the very low processor speed and the small quantity of memory, it was still possible to show studio-quality, full-motion video. Displaying video was accomplished by installing special cards in the computer to overlay the video image with computer graphics. The video was recorded on a videodisc. Finding the correct images for a lesson and displaying them on the screen was managed by the instructional software. Each videodisc contained up to 54,000 frames that could be played either as motion sequences or as single-frame images overlayed with computer graphics. The computer could be programmed to control the videodisc player so that the appropriate video sequence could be displayed in response to student input. For example, students could select reagents to be mixed, and the result could be shown with studio-quality video on the computer screen. Because interactive video allowed users to switch easily between experimental techniques, it was possible to write instructional programs that allowed students to choose a combination of equipment and strategies to develop a concept.

Figure 8. The kind of video that students could see on an IBM XT.

The ability to show full-motion video under program control allowed students to interact with images of real chemical systems that were too expensive, complex, or hazardous for them to do in a wet lab. As a result, the content of the course was both extended and enhanced. Freshman chemistry courses were revised to use a combination of hands-on laboratory experiments and videodisc-based simulations. The traditional laboratory work allows students to refine their laboratory skills while the computer simulations address the intellectual components and concept development. Studies on control groups showed that students who used the combined laboratory and computer simulations did better on a post-lab quiz than those who just did the traditional wet lab (14, 19). Along with the IBM microcomputers came the ability to set up local area networks. The hardware available in the late 1980s produced PC networks that were too slow to deliver video, and so a videodisc player was required for each microcomputer. However, the network could be used to record a student’s progress through the lessons. Special course management systems were developed so that instructors could monitor students’ work. This made it possible to assign lessons and give course credit for their completion. Although this system allowed for the development of highly interactive, instructional material that was educationally effective, the cost was too high for general use because of the need for a videodisc player at each station and the special cards in each machine to mix video with computer graphics. Digital Video In the early 1990s, microcomputer CPU speeds and screen resolutions had increased enough so that it was possible to replace the analog video from the videodisc player with digital video. The major advantage of digital video was that it required no special hardware in the student’s machine. This greatly reduced the cost of delivering instructional material in which students interacted with real images of chemical systems. The digital video could also be networked over a 10 MB segmented Ethernet system. Since the digital video resided on a server instead of separately on each microcomputer, the costs of a complete student station and maintenance of the software were reduced (15). This technology made it possible to develop a visually intensive system of instruction for microcomputers. For example, in studying gas laws, students adjust the volume of a thermostated gas, measure its volume and pressure, and then try various ways of plotting their data to determine the relationship between pressure and volume. These programs utilize the microprocessor on a student’s computer, but the lessons are stored on a network server or CD (16). This provides a rich environment for the develop-


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Figure 9. Series of images showing how students collect gas-law data.

ment of instructional strategies and rapid response to student input. Such a local area network can support at least 200 simultaneous users while providing nearly instantanous access to video images. However, unlike the World Wide Web, access is not universal, and programs such as these do not run in a Web browser. Use of the material from off-campus locations is difficult. World Wide Web Recently the World Wide Web has received considerable attention because it provides nearly universal access to networked material on a variety of platforms. Hypertext markup language or HTML, used to prepare material for the Web, was designed primarily as a way of distributing documents and images. Although this works well for lecture notes, it is not optimized for writing interactive, instructional programs. In order to use the Web for instruction, there must be more components than just well illustrated lecture notes in online courses.

CGI Scripting Methods such as CGI (Common Gateway Interface) scripting were developed to allow some interaction between an end user and the Web server. Using scripting, an HTML page containing a form with questions to be answered and a box for student answers was delivered to students. To judge a student’s answers to a question, the responses are sent to the server where they are analyzed. A new HTML document with feedback, score, and correct answers is generated and returned to the student. This often results in heavy loads on the server and poor response times. Tutorials were designed for mainframes and microcomputers so that there would be no more than 0.2 seconds between the student submitting an answer and the computer responding. The Web is often slower than this. Therefore, this type of computing environment does not work well for the interactive software developed in the 1970s and 1980s. When CGI scripts are used, each interaction between the student and the software requires that the student submit a request to the server for processing before the server sends the student the next page in the tutorial. Even though this is not suitable for tutorials, such a system can be used for judging quizzes, homework problems, and questions where students complete the assignment and then submit it once for judging. Delays in processing the student answers are short compared to the traditional method of turning a paper in for grading. Using this capability of Web-based systems has made it possible to augment traditional courses with online quizzes, grade books, 1084

bulletin boards, and lecture notes. Some course management system programs contain all of these tools for creating Web-based instruction.

Web-Based Course Management Systems Many programs that make it easy to produce complete online courses running on the Web are available. Products such as these use a combination of CGI scripting, Java applets, JavaScripting, and compiled programs that execute on the Web server to create an environment that can be successfully used to teach students. WebCT, developed at the University of British Columbia, is illustrated here. This system allows instructors to post a course calendar, manage a bulletin board, post lecture notes, and give online quizzes. Course managment systems such as WebCT include simple ways to construct quizzes that make it easy to use short-answer, numerical, matching, or multiplechoice questions. Questions can be randomly selected from banks of questions. Partial credit may be given for selected answers. Online Lecture Notes Lecture notes, which can be used both in class and on the Web where students can access them, can incorporate the latest display technologies, including pictures and movies. Using the Web in this way provides an easy way to enhance lectures with images of actual chemicals, equipment, and reactions. Combining all of these features gives a course with a lecture in which presentations are made with projected computer displays. In addition, an organic chemistry course can have each reaction type illustrated by an animation using Organic Reaction Mechanisms by Andrew Montana and Jeffrey Buell (17 ). Spectroscopy is presented with SpectraBook by Paul Schatz (18). A molecular modeling program is used in class to show three-dimensional structures. Outside of class, students use the local area network to access tutorials and simulations as well as all of the display material used in class. The tutorials, which run only on a local area network, provide students with individualized help as well as lots of practice problems. Surveys show that students strongly support this use of instructional technology. In one study done in 1996, 81% of the students preferred using projected computergenerated displays (Power Point) compared to an over-



head projector. The tutorials, which provide more interaction than the Web- based material, were supported by 95% of the students. The data in Figures 10 and 11 show the results from two questions from a survey run in 1998 which indicates that students like having class notes available on the Web and that they find online quizzes helpful. Recent Web Developments Developments such as Dynamic HTML and Java Script now make it possible to analyze student responses on the local machine instead of sending the information to the server for processing. This provides the same kind of dynamic interaction from Web pages that was possible on early mainframe computers and microcomputers running on a local area network or CD-ROM. For example, in a simple nomenclature problem, common wrong answers may be detected, and since the analysis is done on the local machine, the appropriate feedback can be given immediately. Drag and drop technology in a Web browser with local processing makes it possible to engage students in the task of constructing equations, showing how to interconvert the compounds shown with the reagents on the screen. The use of computing technology that uses the local processor extends the capability of the Web from providing traditional documents and grading homework assignments and quizzes to highly interactive, instructional material. The document delivery capability in standard HTML combined with Dynamic HTML make a new type of learning environment in which the student has easy access to both traditional textbook presentations and animations, tutorials, and quizzes—all within the same Web-based instructional system. When Web access is through a low bandwidth modem, there can be unacceptable delays associated with large still images or video clips. Until bandwidth is available that can support rapid access to high-quality images in response to student input, this medium will lack the visually intensive properties of client server or CD-ROM-based programs. The ability to integrate the traditional text material with online homework, quizzes, animation, tutorials, and record-

Figure 10. Survey on use of online lecture notes.

Figure 12. Reaction drill in a Web browser.

keeping into a universally accessible medium has the potential to dramatically change what we teach, how we teach, and where we teach. Literature Cited 1. Lagowski, J. J. In Computer-Assisted Instruction, Testing, and Guidance; Holtzman, W. H., Ed.; Harper & Row: New York, 1970; pp 283–298. 2. Steinberg, E. R. Teaching Computers to Teach; Lawrence Erlbaum Associates: Hillsdale, NJ, 1991. 3. Smith, S. G. J. Chem. Educ. 1984, 61, 31. 4. Alpert, D.; Bitzer, D. L. Science 1970, 167, 1582. 5. Smith, S. G. J. Chem. Educ. 1970, 47, 608. 6. Smith, S. G. J. Chem. Educ. 1971, 48, 727. 7. Smith, S. G.; Sherwood, B. A. Science 1976, 192, 344–352. 8. Moore, C.; Smith, S. G.; Avner, R. A. J. Chem. Educ. 1980, 57, 196. 9. Chabay, R.; Smith, S. G. J. Chem. Educ. 1977, 54, 745. 10. Moore, J.; Gerhold, G.; Breneman, G. L.; Owen, G. S.; Butler, W.; Smith, S. G.; Lyndrup, M. L. J. Chem. Educ. 1979, 56, 776. 11. Smith, S. G. J. Chem. Educ. 1984, 61, 864. 12. Avner, R. A.; Smith, S. G.; Tenczar, P. J. Computer-Based Instruction 1984, 11, 85–89. 13. Jones, L. L.; Smith, S. G. Pure Appl. Chem. 1983, 65, 245– 249. 14. Smith, S. G.; Jones, L. L. J. Chem. Educ. 1989, 66, 8–11. 15. Smith, S. G.; Stovall, I. K. J. Chem. Educ. 1996, 73, 911–915. 16. Smith, S. G.; Jones, L. L. Falcon Software, 1 Hollis Street, Wellesley, MA 02181, 1998. 17. Montana, A. and Buell, J. Falcon Software, 1 Hollis Street, Wellesley, MA 02181, 1996. 18. Schatz, P. F. Falcon Software, 1 Hollis Street, Wellesley, MA 02181, 1990. 19. Smith, S. G.; Jones, L. L.; Waugh, M. L. J. Computer-Based Instruction 1986, 13, 117–121. 20. Avner, R. A. In Issues in Instructional Systems Development; O’Neil, H. F., Ed.; Academic Press: New York, 1979; pp 133–177.

Figure 11. Survey on use of online quizzes.


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From Mainframes to the Web: 1998 George C. Pimentel Award

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