check this out:
http://www.trombonelessons.com/
This site is run by Tom Gibson who is the t-bone prof. at Georgia State and one of the cooler guys you'll meet. I have been doing his daily routine (modified for CC tuba)
and it feels like it's paying off for me. It's real basic stuff, but it's presented in such a way that you can get you arms around it and his instructions are really helpful and would be great for students as well. He also has links to tons of resources, articles and tons of other good stuff. My favorite is:http://www.lightlink.com/bbm/whotjazz.html
cool, enjoy,
Bill Pritchard