Street-Fighting Mathematics
MIT OpenCourseWare offers this Independent Activities Period course on estimating answers and solving problems without formal proof or exact calculation. Lessons cover extreme-cases reasoning, dimensional analysis, successive approximation, discretization, generalization, and pictorial analysis, applied to mental calculation, solid geometry, musical intervals, logarithms, integration, infinite series, solitaire, and differential equations. Materials include lecture notes, assignments, and exam materials drawn from the MIT class taught by Sanjoy Mahajan. The course treats approximation as a rigorous skill in its own right, useful for checking whether a calculated answer is even plausible before trusting it. Free to access online with no certificate offered, following MIT's standard OpenCourseWare format of self-paced study from posted course materials.