Six reasoning tools to make hard problems easy

Here are some MIT physics, mathematics, and engineering courses that I've offered emphasizing a street-fighting approach (the course materials are available at the given links).

18.098/6.099. Street-Fighting Mathematics (MIT, IAP 2007, 2008, 2009) | OpenCourseWare site.

6.055/2.038. Art of Approximation in Science and Engineering (MIT, Spring 2008, 2009, 2010) | OpenCourseWare site.

6.003. Signals and Systems (MIT, Fall 2007)

8.298. Lies and Damn Lies (MIT, IAP 2006)