Automating Assignment Delivery on the
World Wide Web
Larry Martin and Aaron Titus
Physics teachers have been using electronic media in their teaching
for some years. Computers, in particular, have been quickly adopted
into physics classrooms, because it is a natural extension of using
computers in our research. With a wide variety of computer platforms
has come a wide variety of pedagogical software of varying usefulness.
With the advent of the World Wide Web and its cross-platform capability,
a new tool has become available to deliver instruction any time, any
place, to any platform. Much of the initial development of this new
medium was driven by the needs of our research community to deliver
research results electronically so that dissemination among experts
could occur more rapidly than traditional publishing might allow. It
seems natural to extend this widely supported technology into our classrooms.
Early uses of the Web in teaching have sometimes derisively been
called "shovel-ware," meaning that traditional syllabi and
lecture notes were simply exported to Web sites. As new methods became
available on the Web, they were less likely to be adopted because of
the difficulty in learning and using them. For example, as "forms" became
available, the difficulty of learning to write the needed hypertext
markup language (HTML) to produce radio buttons, text area boxes, etc.,
was enough to prohibit many from using this technology. Some simple
forms have been used but often the extent of the post-processing was
to email the results to the teacher, which was no more desirable than
asking teachers to collect more papers to grade. What is needed is
a way of generating the forms automatically and then collecting the
results and grading them automatically. It is also desirable that the
questions have some element of randomization so that student collaboration
is limited. Such power is available through the use of a common-gateway
interface (CGI), a program that runs on the Web server to create Web
pages "on the fly" for display on the student's Web browser.
The CGI may also handle collection, storage, and grading of the students'
responses.
For several years at North Park University, and more recently at
North Carolina State University, we have been developing and using
such programs to aid in the delivery of interactive instruction. This
article describes a program called WWWAssign (often pronounced as "Web
Assign"), freely available from our Web site, which allows relatively
easy construction of lists of questions ready for automated Web delivery
and grading. This CGI is written in Perl and is fairly readable by
anyone familiar with programming. Such assignments have been by us
as homework, tutorials, quizzes, tests, and even exams. The formatting
of the questions into HTML form is handled by the CGI which has been
used successfully on Unix, Macintosh, and PC webservers.
For any assignment, there is a descriptor file containing basic information
about the assignment, including a pointer to a file of names of students
allowed to take the assignment. The students at our institutions log
in using their normal user names and passwords, so there is no need
to create new passwords.
Other information in the descriptor file is carefully annotated.
An advantage of our program is that an assignment may have multiple
sections, making it possible to present information in a later section
which may "give away" an answer to a previous section; however,
the student may not "go back" and fill in another answer
since it has already been submitted.
Four modes of questions are presently supported: multiple choice,
fill-in-the-blank, numerical and essay. All but the last are automatically
graded, and essays may be teacher-graded through a simple Web interface.
The basis of an assignment is a flat text file of questions and answers
with a few simple formatting constraints which allow the CGI to determine
the mode of the question. The format of the source file is line based,
with one line for each question, followed by a single line containing
the answer.
The default question mode is multiple choice (of which "true-false" questions
are a subset). The question is typed on a single line (including any
HTML for extra formatting or links to pictures), followed by the correct
response, and as many distractors as desired. From the question, the
WWWAssign CGI will produce a "radio-button" form with the
positions of the correct answers and distractors suitable randomized.
A fill-in-the-blank question creates a text box for the student's
answer. The answer line contains all possible correct responses separated
by tabs. The program will not accept misspelled answers; the match
must be exact. A numerical answer line contains the correct number
and the proper units. The default tolerance is plus or minus 1 percent,
although an override tolerance may be added. For essay questions, the
answer line starts with two numbers specifying length and width for
the text box. These indicate an expectation for the length of the response.
An exemplary answer may be added; this will appear to the students
when they receive their graded key. The essay grading interface presents
students' responses anonymously to the instructor to preserve some
measure of objectivity. A new type of tagging on questions is used
to created randomized questions. Each student may be given a set of
random numbers in their problems. Several examples of the use of this
method are available on our Web site.
Our experience is that these Web-based assignments are popular with
students, since they can receive immediate feedback on their score.
They also appreciate the fact that they are now forced to keep up on
the reading and classwork by the regularity of the assignments. Such
attention to "time on task" has been severely limited in
the past due to teachers' inability to collect and quickly grade papers.
Students will rarely heed the advice "do it anyway" unless
they know it has a direct impact on their grade. This program allows
students to complete assignments anywhere, anytime, on the platform
of their choice.
We offer this program to the academic community in the hopes that
it may be of service in our common task, that of creatively engaging
our students in investing their time and talents to learning our discipline
and becoming a part of our community of scholars. Information, documentation,
and the program are available from [http://www.northpark.edu/~martin/WWWAssign].
Larry Martin is professor of physics at North Park College in
Chicago, and Aaron Titus is at North Carolina State University, Raleigh.
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