Teaching Tools:
Maplets, AsciiMathML package

Maplets. Maplets are a new tool (developed by MapleSoft) that provide a graphical user interface (GUI) to the Maple kernel. The only downside is that you have to have Maple 10 (or later) installed on your local machine.

You can also run it on a remote server, such as calclab1.math.tamu.edu, if you have a way of displaying the output to your local machine (e.g. through NX). This is a problem shared by the Matlab GUI's also ...

Maplet Videos online demonstrations of maplets teaching mathematical concepts.

AsciiMathML Package:

Developer's Page

AsciiMathML is a way to render mathematical expressions, in real time, using MathML. The syntax is straightforward - you can enter LaTeX expressions surrounded by back-quotes `` or you can surround you math text by the key words 

amath
....
endamath
Some samples can be found here

One additional feature which is very useful is the ability to interactively graph using the SVG (scalable vector graphics) package.

A clever use of Javascript to symbolicly differentiate can be found here If you look at the various javascript libraries that are read in, you can see that the author has used his computer science background to write a parser based on javascript.