With my job, something was not quite right with my software and I could not find the problem. Watching these video lectures, I was able to verify that the math was being done correctly and eventually located where the problem was.
Dr. Strang's video lectures sure helped me and my company.
FYI
MIT Launches Web Site for High School Students
Uses successful MIT OpenCourseWare model to engage high school math and science students and faculty
CAMBRIDGE, Mass., Nov. 28 - MIT President Susan Hockfield today announced the launch of a new Web site, Highlights for High School, that will provide resources to improve science, technology, engineering and math (STEM) instruction at the high school level.
http://ocw.mit.edu/OcwWeb/web/home/home/index.htm
I’ve been watching Stang too, for my studies. He’s a great teacher.