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Teaching with Technology
James P. Birk Arizona State University Tempe, AZ 85287
Using the Internet to Individualize Laboratory Questions
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Steven D. Gammon* and Sharon G. Hutchison Department of Chemistry, University of Idaho, Moscow, ID 83844-2343; *
[email protected] As is the case at many universities and colleges, we use general chemistry lab experiments for more than one semester. We have observed that after prelab and postlab questions have been assigned once, students take advantage of having access to graded responses. Because of this, a typical scenario is that five minutes before the lab period, clusters of students are observed madly copying the prelab answers from an old lab report or sharing their answers. A similar scene is often acted out for postlab questions. To overcome this problem, we have been using individualized, computer-generated prelab and postlab questions. The idea of using computer-generated questions for distribution to students is not new. Morrissey et al. reported their use of computer-created problem sets that are produced for each student and distributed in class. The answers to these problem sets can be submitted online or in writing and are graded as correct or incorrect, with no partial credit (1). A number of other programs are available that present questions for online completion (2). The individualized pre- and post-laboratory question sets that we use are accessed by students from the course Web site and are displayed and printed using a Web browser. The question sets are hand-graded, with partial credit, by the student’s laboratory teaching assistant (TA). Project Description The computer programs that we use to create the preand post-laboratory questions employ Microsoft Visual Basic (VB) script as the programming language and Microsoft’s Active Server Page (ASP) server technology. We currently are running the ASP pages on a system using Microsoft Internet Information Server (IIS) version 4.0, with Microsoft NT 4.0 as the operating system (3). To track the students and assign questions, we use a comma delimited text file (CSV) that can be created in any program capable of saving files in text format (we use Microsoft Excel). For the prelab and postlab question files, any program capable of saving files in HTML format may be used; we use Microsoft (MS) Word and save the file in HTML format. Students may access the questions via the Internet from any type of computer equipped with a Web browser. To use the system, the instructor must write an HTML source file that contains the prelab or postlab questions for a particular lab. This is accomplished using a word processor to write a question file containing all the potential questions for the assignment and a small set of markup commands. The markup commands allow for custom question selection, random number generation, setting significant figures, and formatting the output to the Web browser to facilitate printing. The markup language can be used to create groups of questions of similar nature so that a student using the program is limited to getting only one question of a particular type. The supple412
mental materials contain a sample question file (HTML format) that contains examples of every markup command.W Once an instructor has created the question file, it is placed on the Internet server to be automatically processed by the ASP page. Prelab assignments become available during the week prior to the lab and remain available until all sections have completed the laboratory. The assignments can be viewed and printed from any computer with network access and a printer connection. To prevent students from coming to lab with their postlab assignments already done, we have restricted access to postlab questions to only our laboratory computers. Students print out their postlab questions while the laboratory is in progress. For each assignment, the program accesses the CSV file containing the names, identification numbers, and passwords for all the students. After a student gains authorized access to the system, the program randomly selects the questions from the question file for that student. The student then prints out the list of questions, which has the student’s name automatically printed at the top of each page. Each time a student signs on he or she will receive the same set of questions. This feature is particularly important for defeating those students who will keep trying to obtain a set of questions that is like that of their lab partner. For problems that contain random numerical values, a new set of values is generated each time a student visits the Web page. Because laboratory TAs hand-grade responses, students must show their work, provide written explanations, and use significant figures and appropriate units. The TAs are expected to understand the material that is being covered in the laboratory and therefore are responsible for the answer keys to the question sets. They have access to the question sets prior to the laboratory and are free to ask the course instructor or laboratory supervisor for help on any of the questions that they do not understand. Laboratory TAs who have taught using both the traditional method (everyone with identical questions from the lab manual) and this approach have commented that students are coming to lab better prepared having done the Web-based questions. The TAs have also stated that the individualized problem sets do not take significantly more time to grade than the traditional problems; once the solution to a numerical problem is written out, correct setups to the same problem using different numbers are easy to recognize. In the case of the postlab questions, students are spending more time discussing the questions with each other and the instructors, rather than just writing down the same answer as everyone else. The major advantage to instructors of using this type of system is that it requires computer expertise only on the part of the developer. Generation of the question file requires just an understanding of the program markup language (not
Journal of Chemical Education • Vol. 78 No. 3 March 2001 • JChemEd.chem.wisc.edu
Information • Textbooks • Media • Resources
HTML) and access to a word processor that can save files in HTML format. At the University of Idaho, we have proven the point: Gammon was the developer, and Hutchison, who is neither a programmer nor HTML fluent, has been primarily involved in creating the question files. Hutchison can operate independently of Gammon because the program operation requires only the correct question file with our subset of markup information. Thus, modern word processors that “speak” HTML have lowered the barrier to using this system to the point where it can easily be used by most instructors. Conclusion Removing the copy factor from pre- and post-laboratory question sets has led more students to spend time thinking through what they will be doing and what they have done in lab. Consequently, they are coming to lab better prepared and leaving lab having learned more because they did their own work. Creating the question file using markup characters to individualize questions takes only a few minutes longer than creating the same question set that is not individualized.
Another advantage of this system is that it allows student access to the question sets via a Web browser, which, in the current instructional computing environment, has become the multiplatform operating system of choice. If an NT server is available, the implementation of this system is straightforward. W
Supplemental Material
The supplemental materials available in this issue of JCE Online describe the hardware and software requirements and provide a sample package for deployment. Literature Cited 1. Morrissey, D. J.; Kashy, E.; Tsai, I. J. Chem. Educ. 1995, 72, 141–146. 2. Tissue, B. M.; Earp, R. L.; Yip, C. Chem. Educator 1996, 1 (1). 3. NT Server, version 4.0; Microsoft Corporation: Redmond, WA, 1996–1999.
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