AMC8 past papers
http://www.artofproblemsolving.com/Forum/resources.php?c=182
http://en.wikipedia.org/wiki/American_Mathematics_Competitions
The Official AMC Home Page - http://www.unl.edu/amc/
Complete Archive of AIME Problems and Solutions -
http://www.artofproblemsolving.com/Forum/resources.php?c=182&cid=45
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