Notation Station is a powerful tool for music educators because it allows teachers to use the Internet to distribute individualized lesson plans and compositions to students. Simply create a musical lesson plan or exercise, upload it into the Notation Station and it is available for your students to access, hear, and modify. Your students then return the completed exercise back to you for your evaluation.
A Practical Guide to Music Composition
An entire book on Music Composition made freely available online by the author, this site is useful as a textbook for teaching would-be composers. It assumes readers already know instrumentation and how to harmonize, and goes through topics like progression, structure, all the way to the coda. This site provides a helpful glossary of forms used in composition.
Practical Music Theory
Work your way through the several online books to help teach others about music theory. Read the articles section that carries content ranging from Villa-Lobos to Thirteenth Century Polyphony. An extensive quiz section to test your knowledge of music theory and music exercises that you can practice online if you have a Java-capable browser.
The Random Music for Y2K Project
If you are tired of the standard music theory sites, try looking up this truly fascinating page that offers you an opportunity to compose music onsite. You can also download different programs to create music, or you can choose to just listen to the MIDI collection. It's great fun for lovers of modern music.
Solomon's Music Theory and Compositional Resources
This site is a collection of online music theory and composition resources compiled by music professor Larry Solomon. Much of the provided links are aimed more towards advanced music students.