In this page, you will find a (growing) collection of problems, discussions, and strategies. (You may subscribe to our website for the updates).
AMC 8
AMC 10
AMC 12
AIME
Math Counts
Duke Math Meet
USAMO
Putnam
USAJMO
Physics Olympiad Problems
Magnetic Field at the Center of a Ring
Work Done on Compression of Gas
Specific Heat of a Rigid Triangular Molecule