Baylor Problem of the Month Save
Monthly problems with archive and results.
http://www.baylor.edu/math/index.php?...   

Bradley University Problem of the Week Save
Weekly math problem and archive from Professor Alberto L. Delgado.
http://bradley.bradley.edu/~delgado/p...   

Dansmath Problem of the Week Save
Weekly math problem, with solutions, archive, and leader board.
http://www.dansmath.com/probofwk/prob...   

Hamline University Save
Monthly problems.
http://www.hamline.edu/~math/aguetter...   

IBM Research Ponder This Save
A monthly on-line competition hosted by researchers at IBM.
http://researchweb.watson.ibm.com/pon...   

John Handley High School Problem of the Week Save
Weekly math problem with solutions and archive.
http://www.pen.k12.va.us/Div/Winchest...   

Ken Duisenberg's Puzzle of the Week Save
Problem archive and puzzle links.
http://ken.duisenberg.com/potw/   

Macalester College Problem of the Week Save
Weekly math problem and archive from Professor Stan Wagon for first-year college students presented by the Math Forum.
http://mathforum.org/wagon/   

Math Forum: Algebra Problem of the Week Save
Past archive and solutions. Receive help from a mentor. Paid membership required to view problems.
http://mathforum.org/algpow/   

Math Forum: Discrete Math Problems of the Week Save
Past problems and solutions, student recognition. Paid membership required to view problems.
http://mathforum.org/library/problems...   

Math Forum: Geometry Problem of the Week Save
Past archive and solutions. Receive help from mentor. Paid membership required to view problems.
http://mathforum.org/geopow/   

Math Forum: Math Fundamentals Problem of the Week Save
A weekly interactive project for elementary school mathematics. Past problems, solutions, and student recognition. Paid membership required to view problems.
http://mathforum.org/funpow/   

Math Forum: Problems of the Week Save
Projects from the Math Forum presenting weekly interactive math challenges to accumulate points for bronze, silver and gold prizes. Individual or class participation. Paid membership required to view problems.
http://mathforum.org/pow/   

Math Magic Save
Devoted to original mathematical recreations with puzzles and links.
http://www.stetson.edu/~efriedma/math...   

Mathematics Problem Solving Task Centres Save
Designed to assist teachers and students in problem solving. Includes problem of the month. Paid membership is required to view archived problems.
http://www.mav.vic.edu.au/members/pro...   

Monthly Problem Save
Math problems and solutions from Math Central.
http://mathcentral.uregina.ca/MP/curr...   

Problem of the Fortnight Save
Twice-monthly problems with archive and solutions.
http://persweb.wabash.edu/facstaff/ax...   

Problem of the Month Save
Posted by the Mathematics Department of Bilkent University.
http://www.fen.bilkent.edu.tr/~cvmath...   

Problem of the Week Links Save
Links to problems of the week sites organized by grade levels.
http://www.wits.ac.za/ssproule/pow.htm   

Purdue University Problem of the Week Save
Weekly math challenge with past problem archives and solutions.
http://www.math.purdue.edu/pow/   

PuzzleUp Save
Weekly math problem with archive and scoreboard.
http://www.puzzleup.com/   

Stony Brook Problem of the Month Save
Monthly math challenge with past problem archives and solutions, and hall of fame.
http://www.math.sunysb.edu/monthly-pr...   

Trent University Problem of the Week Save
Weekly math problems and solutions from Trent University.
http://euclid.trentu.ca/math/dgp/potw...   

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