Below are some links to material I've written for students or myself. No claims of
completeness or correctness is made.
It's amazing how often students sit and stare at hard problems, waiting for inspiration, when there are in fact specific actions you can take to move forward. So here are some general notes I wrote for my calculus class, on problem solving (a distillation of Polya's ideas), and
some specific strategies I've found useful over the years.