Things to include in a demo reel

So I am going into overdrive with pencil tests and finished stuff before I finish up school in May. I know I am going to have one or two really big animation projects assigned but I want to also do some side stuff. My school focuses more on motion graphics and online animation but I want to learn full and limited techniques as well. Have been progressing pretty well and feel confident in my work compared to my fellow classmates. I am just a little lost on what all to include in my demo reel and how finished it has to be. Right now I have a couple good clips and a couple bad clips which equal to about 2.5 minutes of footage (good stuff equals a minute). I want to bring that time up to around 4 minutes of good stuff so I can trim it down to around 2.5 minutes of my BEST work. If there is a site detailing good exercises to build skills please send links. Also, I want to include a lot of pencil tests and not just finished stuff, but I am wondering how rough they can be (tied down or less). Thanks!

My advice is forget about the bad stuff. If you aren’t happy with it don’t even think of using it.

What you include can also depend on what role you are going for. I have always liked videos that show storyboard to final product as a way of showing they understand the whole process.

I recently wrote an article about demoreels that might answer some of your questions: http://www.animatorisland.com/?p=811
What you want to include in your demoreel should always depend on what job you are aiming for.
For character animation:
Generally the 11secondclub.com is a good place to practice and discuss character animation. Weight tests are also nice to see especially if they have a funny little story.