Calling all math teachers with websites: there's a dude out there actually making damn good video tutorials for high school students. His name is Salman Khan and he runs Khan Academy. You can read an article summarizing all the buzz around his project here.
As we know, the traditional approach of teachers imparting knowledge to students during the day then reinforcing it back at home is highly flawed at inner city schools. Poor attendance coupled with students' lack of willingness to do a lot of homework hinders the student. It also harms the curriculum progression, often forcing teachers to spend more time than necessary on certain topics.
"New school" principals are in love with the idea of uploading lesson presentations online to let your kids access them. The problem with this approach is that a presentation is just that, a presentation: you still need someone to guide the student through the work unless the student is a self-learner. Video tutorials have gained a lot of popularity lately but most videos out there are poorly created and too lengthy.
In my opinion, a majority of Khan Academy's videos actually seem to overcome these hurdles. The videos are anywhere from eight to fifteen minutes in length. Salman Khan, who narrates all the videos, is articulate and able to explain complex ideas using simple terms, which is actually quite hard to do. Yesterday, I started linking to his videos on my class website. Here's a sample video.
Of course, you still need students willing to watch these videos online in their spare time. Try working around this roadblock using creative titles for the math videos. I imagine labeling the video for ratios as "2 Girls, 1 Cup" might increase the likelihood of a student clicking the link. Maybe.