Quia! Mathematics Activities
Educational activities for teaching mathematics including concentration, matching, flash cards, word search puzzles, and Java games.

Interactive Mathematics Miscellany and Puzzles
Java-based math resource including articles, puzzles and links.

A+ Math
Interactive math help for K-12 students with flashcards, Math Wordfind, Homework Helper and worksheets.

Colorful Mathematics
Educational software presents advanced mathematics to K-12 students in a game-oriented approach, using coloring and drawing techniques to illustrate concepts from graph theory and computer science.

Pythabacus
Description and instruction of using the ancient Pythagorean Abacus to do arithmetic.

Mathwizz
Interactive math problems for abilities ranging from middle school to university.

Archive Creative puzzles
Interactive puzzle archive with descriptions for puzzle construction and a special childrens puzzle page.

MatheMagic
A collection of mathematical puzzles, jokes and articles.

Mathschallenge.net
A website dedicated to the puzzling world of mathematics and computer programming.

Math Forum
Resources, problems and forum for teachers and students in mathematics.

Brain Teasers and Maths Puzzles
Interactive logical and mathematical puzzles with feedback and detailed solutions.

Logicville
Educational puzzles, brain teasers, and word games such as anagrams, cryptograms, alphametics, doublets, tangrams.

MatheMajik
Indian site featuring calculation tricks and math puzzles.

Polymorf - Symmetry of Polyhedra
A demonstration of the symmetry and transformational properties of the Platonic and Archimedean solids.

iQED!
Lateral puzzles from "Puzzles for the High IQ" author Lloyd King and founder of The Puzzle Wizards SiteRing.

Polyhedra Links
Pastime and activity links for various geometric patterns, polygons and polyhedra by Jill Britton.

Mr Titen's More Than Math
Mathematics teacher provides puzzles for students.

Curious Numbers
A tribute to the lighter side of math including puzzles, humor, trivia, quotes, inspirations, and math links.

The Puzzling World of Barry R. Clarke
Brain teasers, articles and puzzles forum.

Tile Tris
Tile a spheroid working room aperiodically or periodically. Includes free demo download.

Brain Teasers by QBrute
Original brain teasers with solutions.

Magic Math Kingdom
Learn math through games and quiz-oriented tutorial.

The Enigmatic World of Philip Carter
Collection of brain teasers from the author of IQ books.

Perfect Times
Teaches and assesses fluency of multiplication and division tables using online cards. Submit data and compare results.

Mixed Up Math
Logic problems, where equations are mixed up. In various formats like boxes, crosses, diagonals, mazes. Free download.

The Null Set
Puzzles collected by Guy Kindler, most requiring some undergraduate mathematical knowledge. Some hints are provided.

Wu's Riddles
A collection of riddles, puzzles, and technical interview questions, with a discussion forum.

Mathematical Recreations
Detailed exploration of a selection of mathematical topics.

Nick's Mathematical Puzzles
A collection of puzzles, with hints, solutions, and links to relevant mathematical topics.

Paul Hsieh's Puzzles
Logical and mathematical brain teasers, with an indication of difficulty. Hints are provided; solutions are available by email.

The Contest Center
Classic puzzles and riddles requiring only simple logic and elementary math.

Riddles
A collection of riddles and logic puzzles with solutions.

15 Puzzle of Sam Lloyd
Play online Sam Lloyd's "15" puzzle The funny story of this game Mathematical implications of this game Some funny logical problems with the 15 game.

Torus and Klein Bottle Games
Collection of Java-based educational puzzles.

SMSU Problem Corner
Math challenges Southwest Missouri State University in three levels of difficulties.

BCIT Mathematical Entertainment
Famous mathematical problems, puzzles, facts, games and trivia.

Math Puzzles
Logic puzzles and riddles with some solutions.

Alien Tiles
Object of puzzle is to try to get color pieces to create certain patterns in cube.

Alphametic Puzzles
Numerous puzzles, links, puzzle solver, and a generator.

Scott Kim
Puzzles for web, computers, and print; ambigrams.

Sequence Puzzles and Problems
With links to related sites. Compiled by Torsten Sillke.

Clever Games for Clever People
Games that interest John Conway including Rim and Traffic Jam.

Contest Center Cryptarithms
Examples of cryptarithms, with prize competitions for subscribers.

Alphametics and Cryptarithms
Puzzles in which letters or symbols are substituted for the digits in an arithmetical operation like addition.

Alphametics Page
Compiled by Mike Keith. Examples of various genres.

Logic Puzzles
Collection of original numerical-logic puzzles. Many are long and difficult, involve sorting and comparing long lists and are intended to be solved using a good spreadsheet program.

A Primer on Cryptarithmetic
Instructions, examples, references and links.

Ken Duisenberg's Puzzle of the Week Archives
Challenging puzzles and problems.

Mathpuzzle.com
Celebrates math puzzles and mathematical recreations.

Algebraic Math Puzzles
A collection of puzzles at high school level. Does not include answers.

Group Games
Animations that develop the theory behind such puzzles as the Rubik cube.

Free Puzzle Collections
Educational and recreational puzzles for teachers, students and parents. Each puzzle is graded by difficulty and has a hint. Solutions are available to members.

Aha! Puzzles
Puzzles, books, games and tests with designed by Lloyd King, author of "Test Your Creative Thinking".

Storkey: Two Envelope Paradox
A tough but simply defined problem which demonstrates key issues in probability.

Mathproblems.info
Over one hundred and fifty math problems ranging from basic math to differential equations.