International Mathematical Talent Search - Solutions and Comments. Problem Page - Archive of problem sets and solutions from Wisconsin Mathematics, Engineering and Science Talent Search. Prof. W. Kahan's Notes and Problems - Large archive of problems and solutions from Professor Kahan's Putnam Problems Practice Seminar. Singapore International Mathematics Olympiad - Training resources include problems and partial solutions. Tournament of Towns at Toronto - Contest problems and solutions for The International Mathematics Tournament of the Towns. Union College Putnam Club - Problem sets from weekly practice sessions. Problem Writing For Mathematics Competitions - Mathematics problems for middle school and high school math competitions with topics range from algebra and geometry to probability and trigonometry. A Collection of Math-Olympiad Problems - Problem sets from international and national mathematics olympiads.