Teaching with a microcomputer: The current status and what's in store

Will computers replace TA's? Professors? Labs? Should they? A symposium report. Held at the ACS meeting, Washington DC, 1983. Addresses the questions ...
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The title of the symposium was made provocative in order to attract the attention of many who have not yet considered the wromise or the limitations of comouters. We howe that manv who read this article will he challenged to take on some of thk costs and risks inherent in experimenting with a new medium of instruction, and will contribute to the discussion we hope the symposium began. The greater the number of creative minds applied to the problems of chemical education, the better. There are certainly plenty of intellectual challenges for those who attempt to apply computers to the task of teaching.

Teaching with a Microcomputer: The Current Status and What's in Store for the Future Stanley G. Smith University of Illinois Urbana. IL 61801 When considering the current status of computer use in teaching and what's in store for the future one can ask: Can ~rofessorshe replaced? should thev he renlaced? and will thev be replaced? TO answer these qiestions, it is necessary tb define what a com~utercan do for both the wrofessor and the student. The ability of a computer t o put k x t and graphics on the screen, accept and intermet student inout. store and recall data, and duralculation;can he molded'into an interactive instrurtional system (21.The maior limitation on the ability of such a system in instruction is the imagination of the lesson designers and programmers. Typical applications (3) include tutorial dialogs, simulations of experiments, practice problems, data collection, control of experiments, and chemical games ( 4 , . These types of programs have been used to supplement lectures ( 5 1 , pru\.ide interactive homework, and prepare students for laboratory work (6,7). Can Computers Teach? Because of its highly interactive nature and the ability to do animations, the instructional approach used with a computer can and should he very different from that in a textbook or a lecture. For exam~le. . . instead of exolainine,. a ohenomenon . the computer can allow the student to experience it thruugh simulations that are designed to illustrate the imnortant features. When coupled 4 t h tutorial material designed to assure that the student understands the simulation and suitable practice problems the computer becomes a new kind of instructional medium that supplements the approaches available in printed matter, discussions, and laboratory work. In a textbook, for example. words mav be used to describe what happensif you campre& a gas in ;cylinder. The process can also he described in lecture along with wictures. But on a computer each student can, through a sinklation, push the piston in and out and collect data on various pressures and volumes. The experiments can be monitored by the computer and individualized help provided to the student only if needed. Even with something as simple as balancing equations the computer can help by. .giving. a table with the number of atoms of each of the eiements in the reactants and the pro& ucts. As you start to halnnce the equatton computer updates the tahle dynamically so you can see what-balancing an equation really means (Fig. 2). I t is clear that:

A computer is not a lab.

You can do a simulated laboratory experiments on the computer, hut that isn't real laboratory work. You can't burn your fingers on hot glass or discover what something smells like on a computer. And remember, A computer is not a book.

I t is easy to tell the difference between a computer and a book-they are very different media. A computer requires new pedagogical approaches. The e f f e c t i ~ i ~ nofi ~'omputer-assisted s instr~~ction, as with all types of instruction, depends on the content, the way it is presented, and the instructional design. Students seem to like working and learning with a computer (5), and, although studies are still limited, the available data suggests that CAI is an effective teaching tool (8,9,10). Thus there appear to he many circumstances under which a computer can replace a professor. Should Computers Teach? If a computer can teach the same material in less time and with greater long-term retention by students than could be achieved by a teacher, then there is a reasonable argument for replacing the teacher. Anyone who can be replaced by a computer should be. However, we should also recognize that A computer is a tool: good teachers cannot be replaced by a computer. A computer will only replace those TA's, professors, and labs that are limited to those types of things that can he done better on a computer. A good teacher will not be replaced by a computer; a good teacher will use the computer to be even better. The objective is not to replace anybody, hut to do a better job of teaching. The computer, as demonstrated by experiments, does serve that role.

Will Computers Teach? The extent to which computers will he used for teaching is critically dependent on the cost of the hardware and the availability of suitable programs. The rapid proliferation of relatively inexpensive microcomputers that have the capability of supporting high quality instructional material is making CAI generally available (11).In 1975 one had to have access to a powerful mainframe computer just to try to do something with computers in instruction. In 1976 if you could put together an Altair kit you could have your own computer for a few thousand dollars. Now, in 1983, for a few hundred dollars you can purchase a computer that is able to support a wide range of instructional techniques. Furthermore, it is likely that in the near future students will have their own

US. Uic keys: t r 1 2 3 5 5 6 5 ~o balance this equation.

A computer is not a book. A book is passive; a computer is interactive. It is also clear that: A computer is not a lecture.

Lectures tend t o be passive. And: A computer is not a hook.

Books have lots of teat. Computers have animations. Also,

Figure 2. Computer display during equation-balancing drill. Note the table of number of atoms of each type. This is updated as each coefficient is entered. Volume 61 Number 1 Januarv 1984

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computers, just as they used to have their own slide rules. n u l , will u e have ioitware for all oitho5e millionsn1'computers? In 1980 there was hardly any software for teaching chemistry on a microcomputer. Now, in August 1983, John Moore and I have figured out that there are probably about 400 individual microcomputer programs for use in teaching chemistry and the curve is going up very rapidly (Figure 3). The ultimate impact of the computer on instruction depends on how it is used. If the existing course content and instructional techniques are simply programmed into the computer, then it will become just another way to do the same thing. Unfortunately, a reasonable prediction for the future (defined as the the next two years) is 11 more titration simulations 57 more nomenclature drills 113 more multiple-choicequizzes 1 new way to use computers to

help students learn The challenge for teachers who do not want to he replaced by a microcornouter is not iust to write more nomenclatural drills or m~rltiplechoiceq&es hut to develop \r8aystu use this new tool to enhance the content and wdiw uf their courses 111 and to find new ways to help students learn chemistry.

Suppose Every General Chemistry Student had a Microcomputer.

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Ailan L. Smith Drexel University Philadelphia. PA 19104 The supposition in the title of this piece will describe reality for all 1800 entering freshmen at Drexel in the academic year starting in the fall of 1983 and, thus, for the 1200 students enrolled in general chemistry. The decision to require microcomputer ownership was not the Chemistry Department's hut was made after study and planning at the university level (12). I chaired the faculty committee that was charged with the responsibility of exploring present needs for and possible uses of a student-owned microcomouter in the undergraduate " curriculum, developing a set of specifications for the personal microcomputer, and identifying commercially available microcomputers that met or exceeded these specifications. An abridged version of the Microcomputer Selection Committee's report is being published elsewhere (13). The computer selected is a new A o d e oroduct not on the market as of this writing (~eptember,1983). I t operates with a 16-hit microprocessor and has a minimum of 64 Khyte of user-available RAM. The computer system, including the CPU, video

monitor, a disk drive, and software, will he sold to students for $1,000 which can be financed. An important part of Drexel's preparation for using microcomputers in the undergraduate curriculum has been a faculty development effort made possihle by a $2.8 million grant from the Pew Foundation, administered by the Glenmede Trust. Some of the projects (workshops, microcomputer seminars, support for courseware and software development, etc.) are described elsewhere (12,14). Using Microcomputers in Chemistry A recent issue of the Computers in Chemical Education Newsletter contained a descrintion of some nroiected uses of microcomputers in our chemistry curriculum (15). Because microcomouters will be uhased in class-bv-class over the next few years;most of our thought so far ha; been on how to use microcomnuters in freshman chemistrv. The most immediate use for micros will he of the standard applications packages provided with the system: word-processing, an electronic spreadsheet, and graphics capabilities. For example, we are considering requiring all general chemistry students to write up portions of their lab reports using the word-processor, thus enabling us to ask for revisions of both the scientific content and the prose of the report. Ohvionslv insisting on good writing as well as good science req ~ i r e ~ c a r e fthought ul and commitment on the part of both faculty and teaching assistants. Another application I have been interested in is the use of electronic spreadsheets as a computational tool in general chemistry. Much of the content of today's general chemistry course involves calculations-and it should remain that way. While there are manv wonderful chemical ideas whoae essence can be stated without using mathematics-molecular structure, for example-many of these ideas can profitably be elaborated with well-chosen computations. Ideallv solvine for examole those involvine" - orohlems. . aqueous equilibria, requires that students he aware of what chemical soecies are oresent and what chemical reactions are taking place. Then the studem car1 "ser up the problem," that is. rind a lurcical structure that makes the sul~rrionhrrairhtforward. ~ D c this e is done, a linear sequence of instructions can he given to any calculating device to find the answer. Unfortunately, most people don't think in a sequential manner, and the structure imposed on the problem by the linear medium of a programmable calculator with its single-line display often hides from students the key relationships hetween quantities and procedures so important in understanding the problem. ~ n t e r - t h siand-alone e personal computer and an electrunic spreadsheet program like VisiCalc" (a trademark that is an ahhreviation for "\,isiblr rnlculator"~.The voreildshect organizes numeric data in tabular form and allows the use of this data to calculate new rows or columns. If a value in the tahle is changed, all other values that depend on the first one are immediately recalculated and the table on the screen is updated. Rows and columns can be labelled to show clearly what they contain, it is easy to enter or change numeric values, and once a useful tahle has been devised it can be saved as a temnlate for later use. These spreadsheet features are quite attractive for many tvnical eeneral chemistrv calculations. The comoutational capacities of the typical spreadsheet eliminate the need for ad-hoc anoroximations alone the wav to solutions of even complex equilibrium problems. For example, I have developed a soreadsheet temolate to solve for eauilihrium concentrations * of the general chemical reaction

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oA+bB=cC+dD

Figure 3. Graph of number of instructional programs versus time. Data from S. G. Smith and J. W. Moore. 28

Journal of Chemical Education

given initial concentrations and the equilibrium constant. A snecial case of this temolate solves the weak acid dissociation problem. The immediate updating of the whole sheet after

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