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When personal computers first appeared on the education scene there was great excitement over how this technology would revolutionize learning and instruction. Despite sound leadership and demonstrated success at a few places where computers are more fully integrated into the chemistry curriculum [1-4], the expected gains in chemical education for the most part have been an unrealized dream at the college level. Some reasons for this at both large and small schools include faculty skepticism, the absence of suitable software at many institutions, a lack of faculty interest/skill, and/or absence of suitable hardware easily accessed by students and faculty. Government data [5-8] indicate that approximately 50% of enrolled college students own their own computers. Although the percentage is rising annually, many college students (up to 50%) still do not have easy access to computers.
More importantly the type of access and kind of computer usage seems to falls short of the potential for significant educational impact [9]. Word processing is the computer skill attained by most students at all educational levels. Drill type programs or simulations follow as the other typical educational use. If Internet access is available student usage is usually dominated by e-mail or entertainment type chat/news groups. Among college students and even their faculty the Internet is not yet a major force for learning and instruction.
Overall science and mathematics computer applications play a much smaller role in the lives of most students at all levels. Even science majors, including chemistry majors, do not have full integration of computer technology into their curricula. Many undergraduate organic chemistry students, even those at major universities, do not see a computational chemistry exercise in their lecture or laboratory experience. Biochemistry courses, except in rare cases, do not usually use modern protein structural data or computer display of three dimensional structures in class or in the laboratory. The situation in analytical and physical chemistry is not much better. Two or three semesters of these undergraduate courses can and do get taught in many, or perhaps most, places without the use of a computer in the lecture and with minimal computer usage in the laboratory. The topic 'what every chemist should know about computers' was discussed extensively during Chemconf93 (Discussion-All) [10].
Although the same major activities found in the general population dominate the use of computers by chemistry students, there are four other applications that are used by students in upper level courses.
First, computers are used to control instruments, and to collect and process data. This function, however, has the potential danger of being peripheral to the learning of chemistry through laboratory work if students do not actively interact with the data during the collection and processing stages, the infamous `black-box' syndrome [11].
Second, using commercial spreadsheet software for computation and graph preparation may be even more important than the instrument interfacing aspects of data acquisition for most student work, especially in undergraduate analytical and physical chemistry laboratory courses. From this follows the possibility that most, if not all, faculty generated FORTRAN, PASCAL or BASIC software used by undergraduate students to analyze data can and should be replaced by the routine use of commercial spreadsheet packages. Most of these 'in-house' programs cannot be transferred easily to other instructional or work settings where students will be expected to be fluent with commercial software. Furthermore spreadsheets require students to think logically through the data reduction processes.
Equation engines such as Mathematica [12], Maple [13], and Mathcad [14] also provide new and powerful approaches to computation and data analysis in analytical and physical chemistry courses. Many students acquire the requisite skills to use these engines in their calculus courses. Others can learn the essentials in a few hours of study with appropriate sample exercises.
The importance of spreadsheets and equation engines for student learning can not be over emphasized. First, students would be able to do complex derivations and calculations efficiently and accurately [15]. The time saved can then be used to develop further insights into the chemical significance of, for example, titration curves with varying concentration and reaction conditions. Second, they would be able to solve more complex problems with large sets of data. In this category would fall realistic problems coming directly from research laboratories at the home campus or downloaded from distant campuses and industrial centers via the Internet. Third, students will learn not to fear data-rich problems because corrections of errors that might occur during the work-up of the data take only a few seconds to apply to entire equation-engine or spreadsheet documents.
Finally, molecular modeling and computational chemistry are the remaining applications important for students doing and learning chemistry. In a few places these tools are used as an integral part of the inorganic, organic, and biochemistry courses at the undergraduate level. Software such as Spartan [16], HyperChem [17], and CaChe [18] have the type of computing and visual power coupled to a student-friendly interface that promotes learning.
Most of the available uses of computers in chemical education as currently employed at most schools do not move the paradigm of higher education away from its dominant format; namely, the delivery of information through lectures. Some teachers continue to think that lecture is the most efficient mode of instruction, although this opinion may be based more on what they themselves experienced during their academic career rather than on any valid assessment protocol. Other faculty who may be willing to change or experiment with teaching strategies often find themselves locked into the 'lecture mode' through the economics of education and the expectations of the education-consuming public. This is complicated by the fact that costs associated with computers and technology have made delivery of information in the classroom more and more expensive in terms of equipment [19] and teacher time [20, 21].
Computer activities are now, for the most part, added to the traditional lecture format through homework or other out of class activities. If student time and energy form a system with finite limits then this increased load dictates reductions in other parts of the system. The net result is little or no gain in learning. Active-learning strategies [22-24], on the other hand, may provide the answer to this dilemma by providing cost- and learning-effective strategies for optimizing the efficiency of student learning, especially when the students are using computers as stand-alone tools or as a link to the Internet.
It is often asked if computers have a significant impact on the success that students have in learning chemical concepts. Two recent reports shed new light onto this discussion. In the first the use of computer animations about the particulate nature of matter significantly improved student comprehension of the concept [1, 25]. The second study gave evidence that the instructor's teaching epistemology played a central role in the effectiveness of computers as tools for inquiry-based learning [26].
The situation is very different for spreadsheets, equation engines, and molecular modeling programs. When these are used as instructional tools they have a very high potential for taking lecture away from the dominant delivery format toward a more effective active learning one. To actuate this potential teachers need to develop and efficiently share coherent, content-rich learning materials for a wide variety of commercially-available software packages. Moving away from the podium might be a good idea too.
The rapid growth in the use of computers and the Internet over the past few years places chemistry students and their teachers in a unique learning situation. Now more than at any other time in the history of chemical education they may be able to appreciate each other as experts. Students bring technology and computer skills, or a high level of interest in these, while teachers bring chemical thinking skills, concepts, and techniques to the instructional table. A merger of these can motivate chemical learning while more closely tying it to the technology that students naturally appreciate and will be required to use throughout their careers.
The Internet is an ideal forum for the marriage of technology and education. It is a facile vehicle for the exchange of ideas on applications of commercial software in teaching. Through the Internet chemists have within their grasp the potential to revolutionize and enhance the education of chemists at all levels by interactively linking scholars and students with each other and with chemistry learning materials. Although the extent to which the potential of the Internet will be realized is yet to be seen, it is possible to explore some possibilities of how this medium may become increasingly useful.
The role of the Internet in chemical education will undoubtedly continue its helter skelter, multifaceted, rapid development. First, it is a primary avenue for disseminating and archiving information. Departmental and institutional WWW pages already contain html style sheets [27, 28], course and faculty information, syllabi etc. in addition to the traditional school catalogs. Three very good examples include the information contained in pages at the Journal of Chemical Education: Software at the University of Wisconsin [29], the Educational Resource page at the University of Maryland - College Park [30], and the Chemistry Department page at Lebanon Valley College of Pennsylvania [31]. Second, the Internet is used for an exchange of chemical education information and research ideas. Examples of sites of interest to chemical educators include the page describing the NSF [32] funded projects designed to catalyze reform of undergraduate chemistry education, the archives of discussions and papers from the first on-line conference in chemical education, ChemConf93 [33], the development site for ChemConf96 [34], and the Chemed-L [35] among others. Good compendia of sites of interest to chemical educators have been presented by Shaw [36] and Wolman [37] . Third is data base access, development and maintenance. Two examples are Web Elements at the University of Sheffield [38] and the Brookhaven Protein Data Bank [39]. Fourth, is collegial communication. The most important aspects of this, beyond on-line communication between faculty and students, might be collaboration on papers, books, journals etc.; all of these are much easier via e-mail. An excellent expression of this collaboration is the publication of on-line peer-reviewed papers in for example the Chemical Educator [40] or this TrAC/Internet column [41]. These roles of the Internet, however, only scratch the surface of the potential of this medium as a tool for learning and doing chemistry. The greatest impact will inevitably accrue when students use the Internet to interact with and learn chemical concepts. The greatest need is for materials that are written for students rather than for other teachers and/or high end, i.e. resource rich, users. This raises the question of what and how students should learn, in other words, how are content, pedagogical models, Web site construction, and learning linked?
A serious problem in higher education is the absence of matches between the instructional materials used in traditional college courses and the learning styles of a diverse student population [42].
Construction of instructional Web sites where pedagogical principles are coupled to effective Internet style is a challenge. This challenge arises from the fact that most of those who are creating these Web sites are not fluent with the literature about young adult and adult learning styles and the teaching techniques that are most effective with this diverse group. The temptation may be very strong to translate texts and lecture notes into Web pages. This may be a mistake as the learning and study styles of most students are different from those who create the materials and programs [42]. Furthermore, if we merely provide information without the accessory pedagogical tools then we will have succeeded in merely transferring the printed page of the teachers notebook to magnetic/electronic medium. Although the presentation will be more lively with video clips etc., the result for the student will be the same as a plain vanilla lecture because they will not have been given sufficient instruction on how to think critically about the cleverly-presented content.
The most important concern here is the creation of more effective learning environments for students. In order to do this Web site creators must consider the various learning styles and stages of development of young adult and adult students as they interact with course material and develop a mature understanding of a topic. Some of the various models of learning that should form the foundation for Web materials are Bloom's taxonomy [43], the Perry model [44, 45], constructivism [46], the reflective judgment model [47], and the Richard Paul discipline-specific logic model [48]. Each of these can help Web developers to target their creations to students with a wide variety of learning styles.
The Web page creator must also address the challenges offered by rapidly changing technology. This means that in order to meet the needs of the typical college or home user, it may be necessary to maintain alternative sets of resources. This can already be seen at some sites where bandwidth intense files are identified by size and shown first by smaller thumbnail images. The same is true for HTML text files. Many are accompanied by easier to download FTP'able unmarked versions. Choices in graphics or text resolution can also expand or contract the audience for educational documents. Identifying the balance between resolution and accessibility will always be a concern for developers of teaching and learning materials.
The major impact of the Internet on learning and instruction will be realized from the rapid growth of course materials and learning scenarios to supplement or replace text and/or handouts, and even entire lessons prepared by individual instructors. Therefore, good Internet sites must contain more than a set of graphics presentation type images with one or two lines of text. An excellent example of accessibility and economy in style can be seen at the Chemistry Hypermedia Project [49, 50] site maintained by Brian Tissue at Virginia Tech. Another is the NIH Molecular Modeling Gateway [51] in particular the various tutorials on molecular modeling. The concepts in computer-aided drug design can be explored at the site maintained by Stuart Green at Leeds (UK) [52] while those interested in crystallography will find resources at the X-ray diffraction tutorial [53] and Teaching and Education in Crystallography [54] sites. The materials available at all of these sites are accessible to students and could be used by teachers at any school to enrich learning experiences and to free up classroom time for more reflective activities. The extra time could also be used for formative assessment studies that would facilitate construction of improved learning materials, ones that are more responsive to student learning needs.
What is needed is high quality, content-rich, self-paced, interactive materials that are available on demand from various locations on and off campus. Hyperlinked text, audio segments, animations, and exploratory sequences of activities using files in standard commercial software format will permit students to learn while providing links forward, backward and sideways for the student who likes to explore concepts non-linearly. The materials should go beyond the page turner mode of interaction with computer-networked information. The materials should also approach a topic from several points of view and answer the needs of students with different learning styles and at different levels of mastery (see reference [50]). The modules should allow students to move up or down in difficulty level as needed to ensure mastery of the topic. Pointers should connect the viewer to content area and even an appropriate level within that area. This should, last but not least, be coupled to reading lists and problem sets suitable for off-line work.
Web-based educational materials should also provide for some reflection and it might be better not to answer all of the questions that an exercise may present. Something should be left for them to ponder and discover by themselves. After all, one of the goals of effective teaching is to train students to explore concepts or solve problems actively rather than merely to read or hear solutions passively. The frequent student response that they understand what is said or written often does not translate into action that demonstrates functional skills with concepts. Interactive learning with appropriately designed materials via the Internet may ameliorate this problem.
With better designed instructional materials, more effective formative and summative assessment should be possible. Formative assessment time would lead to discovery of flaws in student understanding, in time for correction before summative exams, as well as flaws in the on-line and other class materials used by the students. The classroom in turn can become the performance-based skills development and assessment type of environment typically found on the sports field or in the music studio. Better instructional materials would also contain built in assessment and mastery evaluation exercises for students to use to measure their own progress. Honest self assessment is one of the marks of a mature, critically-thinking scholar. In this scenario exams may finally be able to more accurately measure the extent of student mastery of a set of course objectives and outcomes.
Although Internet usage by students is currently dominated by e-mail, news and chat sessions, some new learning formats for chemistry students are appearing. An example is the on-line course on environmental and industrial chemistry [55] sponsored by the Computers in Chemical Education Committee of the ACS Division of Chemical Education for the Spring 1996 semester. This course is an excellent example of an adaptation for students of the on-line conferencing experiences enjoyed by faculty and researchers over the past few years. During this course students are examining the relationship between chemical industry and the environment in a global society. Students from twenty colleges across the United States are using the WWW to access three papers prepared by industrial leaders and to participate in an on-line dialogue with the authors and each other as they explore and critically evaluate the topics of the expert papers. A faculty mentor at each college is implementing the traditional classroom practices associated with a chemistry course. Faculty are also monitoring the on-line progress of their students and corresponding with each other via e-mail as the course progresses.
The Spring '96 course was preceded by a small trial run [56] during the Fall 1995 semester. An on-line course is a prime example of collegial interaction leading to an enhanced learning experience for students, one in which they will be able to share a depth and style of learning not possible with the traditional one teacher in one classroom.
Classroom experiences should change as a consequence of the expanding Web. Students will be able to explore topics more fully before class as the terse compressed writing of a text book is replaced by expanded multi-tiered on-line learning materials. Reflective discussion of scientific concepts and exploration of tactics for solving more complex chemical laboratory problems will increasingly dominate classroom time. Discussions typical of the work of graduate student research groups will be possible at the undergraduate level as the time needed by teachers for `presenting' topics is reduced. Even the nature of the problems that students will be able to solve will change as raw data from research laboratories becomes WWW available.
Certainly no one teacher can develop all of the on-line materials needed in one course. As the Internet expands more materials will be added and the task of writing for any one instructor will become smaller. This changes the role of the `wired' instructor who will be placed in the enviable position of being able to develop and keep at the cutting edge a few excellent instructional units supplemented with Internet resources for other topics. Evaluation of the suitability of any materials from the Internet will of course still be a primary role for all instructors. Developing these same critical skills in students will be an essential ingredient in the new learning environment.
Paraphrasing Smith [57]: the greatest limitation on the use of the Internet in chemical education will be the creativity and pedagogical wisdom of the Web authors and the Web users.
It seems that through the use of the WWW the walls of the classroom may vanish. In the resulting new, open environment we may be able to soar like learning eagles, but ....., we might also end up on the floor of the Web on all fours. Which is it to be....?
TJZ acknowledges that partial support for this work was provided by the National Science Foundation's Division of Undergraduate Education through grant DUE #9354473 and by the New Traditions project at the University of Wisconsin - Madison through the National Science Foundation's Division of Undergraduate Education through grant DUE #9455928.
( All URLs visited February 28, 1996)
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[10] Chemconf93 (Discussion-All), ChemConference/PostConference/PaperC.WhatChemistsNeedToKnow, Post Conference Discussion of What Every Chemist Needs to Know about Computing and Swift, M.L., and Zielinski, T.J., "What Chemists (or Chemistry Students) Need to Know About Computing." J. of Science Education and Technology 1995, 4, 171-179.
[11] The "black box" problem was discussed during ChemConf93 (Discussion-All), http://www.inform.umd.edu:8080/EdRes/Faculty_Resources_and_Support/ChemConference/ Discussion.all.txt/. Use Find in the Edit menu to locate specific references to 'black box.'
[12] Mathematica is a registered trademark of Wolfram Research, http://www.wolfram.com, 100 Trade Center Dr., Champaign, IL 61820.
[13] Maple and Maple V, http://www.maplesoft.com, are registered trademarks of Waterloo Maple Inc., 450 Phillip St., Waterloo, ON, Canada.
[14] Mathcad , http://www.mathsoft.com, is a registered trademark of Mathsoft, Inc. , 101 Main Street, Cambridge MA 02142, USA.
[15] Some would argue that these programs should be used only after students have mastered concepts in a more traditional fashion. For example, manual graphing should precede computer graph preparation at the college level. Interesting discussions on this can be found in the ChemConfer93 (Discussions-All) that followed Paper#6: http://www.inform.umd.edu:8080/EdRes/Faculty_Resources_and_Support/ ChemConference/Discussion.all.txt. Use find "graph" to search for relevant postings. See also "New Tools vs. Old Methods" Chemconf '93 discussion thread. See also Long, G., Pence, H., and Zielinski, T. J. ,"New Tools vs.Old Methods: A Description of the ChemConf '93 Discussion." Computers and Education: An International Journal 1995, 24, pp 259-269.
[16] Spartan, http://www.wavefun.com/spartan/spartan.html, is a registered trademark of Wavefunction, Inc., 18401 Von Karman Ave., Suite 370, Irvine, CA 92715, USA.
[17] HyperChem, http://www.hyper.com, is a registered trademark of Hypercube, Inc., 419 Phillip Street, Waterloo, Ontario, Canada, N2l 3X2.
[18] CaChe, http://www.ig.com/PRODUCTS/perscache_top.html, is a registered trademark of CAChe Scientific Inc., P.O. Box 4003, Beaverton, Oregon 97067.
[19] Workshops on Critical Issues: Planning and Financing Educational Technology, March 1995: http://www.ed.gov/Technology/Plan/RAND/Finan.html .
[20] Massey, W. F. and Zemansky, R., "Using Information technology to enhance Academic Productivity," http://192.52.179.128/program/nlii/keydocs/massy.html. This is one of the National Learning Infrastructure key documents.
[21] Massey, W. F. and Zemansky, R.., "Information Technology and Academic Productivity." Educom Review, January/February 1996, 12-14.
[22] Twigg, C. A., "Active Leaning: Computers in Teaching Initiative, University of Oxford, UK" Educom Review, January/February, 1996, 56-57.
[23] Active Learning: http://www.ox.ac.uk/cti.
[24] Bonwell, C. C., and Eison, J. A. (1991) "Active Learning: Creating Excitement in the Classroom." ASHE-ERIC Higher Education Report No. 1. Washington D.C.: The George Washington University, School of Education and Human Development.
[25] Williamson, V. M., and Abraham, M. R., "The Effects of Computer Animations on the Particulate Mental Models of College Chemistry Students." J. Res. in Sci. Teaching 1995, 32, 521-534.
[26] Moar, D., and Taylor, P. C., "Teacher Epistomology and Scientific Inquiry in Computerized Classroom Environments." J. Res. in Sci. Teaching 1995, 32, 839-854.
[27] Lynch, P. J., "Web Style Manual." http://info.med.yale.edu/caim/StyleManual_Top.HTML: Yale Center for Advanced Instructional Media.
[28] The HTML Writers Guild: http://www.mindspring.com/guild/.
[29] The Journal of Chemical Education: Software: http://jchemed.chem.wisc.edu.
[30] The University of Maryland-College Park Education Resources: http://www.inform.umd.edu:8080/EdRes.
[31] Lebanon Valley College of Pennsylvania: http://www.lvc.edu/www/chemistry/index.html .
[32] "NSF Grants Serve As Catalyst for Undergraduate Chemistry Reform," http://stis.nsf.gov/nsf/press/pr9546.htm. The projects include: 1. The New Traditions Project, University of Wisconsin - Madison: http://www.chem.wisc.edu/curriculum_development/curriculum.html; 2. The ChemLinks Coalition, led by Beloit College: http://chemlinks.beloit.edu/; 3. the Workshop Chemistry Curriculum, a City College Consortium centered at the City University of New York: http://www.sci.ccny.cuny.edu/~chemwksp/; and 4. the The ModularCHEM Consortium centered at Berkeley University: http://www.cchem.berkeley.edu:8080/.
[33] ChemConf93: http://www.inform.umd.edu:8080/EdRes/Faculty_Resources_and_Support/Chem Conference.
[34] ChemConf96: http://www.inform.umd.edu:8080/EdRes/Faculty_Resources_and_Support/ ChemConference/ChemConf96 .
[35] CHEMED-L Subscription Information: listserv@uwf.cc.uwf.edu;
Contact Address: Bill Halpern WHALPERN@uwf.cc.uwf.edu;
Submission Address:
CHEMED-L@uwf.cc.uwf.edu .
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[39] Brookhaven Protein Data Base Search Strategies via the NIH Gateway : http://molbio.info.nih.gov:80/modeling/net_services.html and the Brookhaven Protein Data Bank.
[40] Chemical Educator: http://chedr.idbsu.edu/ .
[41] TrAC Internet Column: http://www.elsevier.com:80/section/chemical/trac/intntcol.htm.
[42] Twigg, C. A., "The Need for a National Learning Infrastructure", http://192.52.179.128/program/nlii/keydocs/monograph.html. This paper was originally published in Educom Review, ISSN:1045-9146; vol. 29, # 4, 5, 6 (1994).
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[51] The NIH Molecular Modeling Gateway: http://molbio.info.nih.gov/modeling/gateway.html
[52] Green, S., "Computer-Aided Drug Design": http://www.chem.leeds.ac.uk/Project/Teaching/cadd.html.
[53] Proffen, T., and Neder, R., Tutorial X-ray Diffraction: http://rschp2.anu.edu.au:8080/proffen/teaching/teaching.html.
[54] Teaching and Education in Crystallography: http://www.unige.ch/crystal/w3vlc/edu.index.html.
[55] On-line Course in Environmental and Industrial Chemistry: http://www.py.iup.edu/college/chemistry/chem-course/webpage.html.
[56] Zielinski, T. J., "How Hot is That Flame Anyway," http://www.py.iup.edu/college/chemistry/chem-course/trialrun.html and Flame Case Study, http://www.niagara.edu/~tjz/dflame/flame1.html.
[57] Moore, J. W., "Summary and Conclusions." J. Chem. Educ., 1984, 61, p35.
©1996 Elsevier Science bv