CGI Scripts for the Electronic Classroom
A Presentation at the
Teaching with
Technology Symposium
West Chester University, Pennsylvania
May 7, 1998
I am not a computer scientist; I'm a librarian by training, and a college instructor by inclination. Among other things, I teach courses in [archived at the Wayback Machine - 2009] using the Internet at local colleges. The librarian in me wants to make all of my resources as available as possible to my students, and the teacher in me wants to explore all avenues of approach in creating these resources for my students. I've tried many approaches to incorporating the Internet into the courses I teach, and CGI scripts have proved to be some of the most effective, and fun, tools for teaching that I've found.
- What is CGI?
CGI, Common Gateway Interface, is not a language, it is a "gateway"
between little programs that run and perform neat tricks and the hypertext
server. CGI scripts are written in a variety of languages, including C,
Basic, and Perl. All of the scripts I use are written in Perl, and I
believe it is most common language used.
Web pages written in HTML are static -- they do not change. CGI allows interactivity. With CGI you can have fill-out forms, page counters, search engines and other nifty tricks.
- Examples of CGI Use in Teaching
Here are a few CGI script examples and how I use them.
- My newest trick is the [no longer viewable - 1009] pull-down menu
on my UNCA Internet class page. I like this approach because it allows
me to "stack" a number of links in a small amount of space. Since my
classes are largely based on the Internet, this pull down menu is a
compact approach to providing access.
- I provide my students with an [archived at the Wayback machine - 2009] anonymous
comment form. It's my hope that I can be alerted to problems during
the semester when there is time to implement solutions.
- In order to attend this conference I had to miss one final exam! This
is usually an unforgivable act at my school. But I realized last month
that I could give the test as a fill out
form. [archived at the Wayback machine - 2009] The results were emailed to me;
I graded the tests and emailed the grades to my Chair, who will carry the
grades over to the Registrar for me tomorrow.
- Dr. Tom Treadwell, here at West Chester University, runs a webboard [no longer viewable - 2009] for his
classes, which I helped to set up. For various reasons an email-based
discussion forum was not an option. So we built this set of web boards for
his students to use. If you'd like to experiment with a webboard, try my
graffiti board [no longer viewable - 2009]. It is erased periodically, and
anything goes!
- I run a
search engine to search my web site [moved to The Flying Cat - 2009] and it's one of my most
successful and rewarding efforts. Not only does it help my students
locate specific information in my site but it generates a log of searches performed
[no longer viewable] which I use to
make my site more accessible. For example, it had not occurred to me
to use the word "classwork" on the assignment page. But once I saw a
search for this term I included it in the meta tag for the page.
- The Online
Notepad [archived at the Wayback Machine - 2009] is a handy place to take notes that can then be mailed to
yourself (or anyone).
- The Neverending Story [no longer viewable - 2009] always draws out the creativity in all students!
- With another kind of CGI script you can display random quotes on
your pages.
Censorship, like charity, should begin at home; but, unlike charity, it should end there. -- Clare Booth Luce
- I found a script that allows me to present my own "404 File Not
Found" page. It's nice to be able to offer alternatives when a person
hits a bad link to something on one's own site. Try this non-existant link
to see the page.
- The AXS Visitor Statistics by Fluid Dynamics off a terrific way to see what areas of your site receive visitors. This sample AXS report shows only a few of the reports that are available.
- My newest trick is the [no longer viewable - 1009] pull-down menu
on my UNCA Internet class page. I like this approach because it allows
me to "stack" a number of links in a small amount of space. Since my
classes are largely based on the Internet, this pull down menu is a
compact approach to providing access.
- Security Issues
CGI scripts are a two-edged sword. They can present a security risk,
but they're so useful that it is worth the trouble to make sure the
scripts are safe to use. The danger in CGI scripts is that they are
executable programs that allow direct access to the server.
The best way to be sure the scripts you use are safe is to ask your system administrator or some other trusted programmer to review them. Selena Sol, a terrific CGI programmer and the Online Services Coordinator at the Electronic Frontier Foundation has written an excellent essay on CGI security issues. The NCSA has a collection of security tips and hints. The W3.org offers a FAQ on Web security that includes very clear explanations of security ricks associated with CGI.
Keep track of where your scripts come from and keep an eye on those sites for updates and improvements.
- Where are the script archives? - links not checked for Some Time
- A collection of CGI script archives
- The CGI Resource links an entire section for tracking visitors to your site.
- Scripts for educators
- Selena Sol's Extropia is a terrific source for scripts.
- I use a lot of scripts from Fluid dynamics
- Cliff's Perl Scripts is another good source of scripts.
- Jon's CGI Scape is yet another excellent source of perl scripts!