HEATKEYS

Enjoy an awesome range of free math games, interactive activities, practice exercises and cool problem solving challenges that are perfect for kids learning math as well as teachers looking for fun, educational resources online.

Hundreds of free, printable sudoku puzzles at all levels, ranging from very easy to extreme.

Excel templates, calendars, calculators, spreadsheets, and other Excel solutions for business, home, and educational use.

Sudoku! Everything you need to know about this addictive puzzle. Come for the knowledge. Stay for the fun.

Sudoku - The Latest Puzzling Craze. Complete Puzzles - 6x6 or 9x9 and use the Puzzle Solver. Find out about the History and Origins of Sudoku

Play Sudoku online from easy to evil. Web Sudoku also supplies Sudoku puzzles for newspapers, magazines, Sudoku books and websites.

Strategies for Sudoku, Sudoku X, Killer Sudoku and Jigsaw Sudoku - and the home of logical puzzle maker Andrew Stuart

Instructables is the Biggest How To and DIY community where people make and share inspiring, entertaining, and useful projects, recipes, and hacks.