Lite Applets

by

Frank Wattenberg
Department of Mathematical Sciences
United States Military Academy
Frank.Wattenberg@usma.edu

Bart Stewart
Department of Mathematical Sciences
United States Military Academy
Bart.Stewart@usma.edu

Suzanne Alejandre
The Math Forum at Drexel
suzanne@mathforum.org

The image above uses the first Lite applet from the MathDL Lite Applet Collection. Distances in Afghanistan is a student-ready module suitable for students in middle school through college using this applet in the context of studying distance or the Pythagorean Theorem.

You can use this applet, called Image_and_Cursor, in a curriculum module just like you would use an image. But this applet gives you more power than an ordinary image. If you click anyplace on the image you will notice that the cross hairs move to the point at which you clicked and that its coordinates appear at the upper right. You can fine tune the position of the cross hairs by clicking on the four arrows -- above, below, to the left, and to the right of the image. This applet can be used in many different ways in many different curriculum modules -- for example, students studying distance or the Pythagorean Theorem could determine the distance between Kabul and Kandahar by finding the coordinates (in pixels) of the two cities from this image, applying the distance formula or Pythagorean Theorem, and then using the scale at the bottom of the map to determine the distance in either miles or kilometers. Or, a calculus instructor might introduce the idea of approximating the length of a curve using a polygonal path by asking students to determine the length of the border between Afghanistan and Iran. The html code including this live image is shown below.

You will need the following files to use this applet.

These files should all be placed in the same directory as your html page. You may want to start with one of the html pages in this article. There are several ways in which you can save an html page in a form that allows editing, depending on your operating system and browser. One sure way that works with all combinations is to choose Source from the View menu, select the enitre text; and then copy it into a new document in whatever text processing program you use for working with html -- for example, Notepad on Windows machines or TextEdit on Mac OSX. You can also paste selected portions of this file into html pages created using programs like DreamWeaver or Front Page.

Lite applets are flexible and powerful tools that can be used as part of highly interactive curriculum modules that are scientifically and pedagogically sound and that can be easily customized. For example, it is easy to substitute another map or image above by changing the file name given by the backdrop_filename parameter and the dimensions of the applet and image in the code above.

The power and flexibility of Lite applets are based on three ideas:

The Lite Applet Collection is open source. All the files including the Java source code files used in this article are freely available and may be downloaded from this site. We invite you to submit your own Lite applets and modules for consideration for inclusion in this collection. Contact Frank Wattenberg or one of the other authors for further infotrmation. We expect to add new Lite applets and new modules using those applets to the collection regularly.

The next section discusses how Lite applets can be used with a spreadsheet or computer algebra system.

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