Conceptis Puzzles contains hundreds of permanent free puzzles.
Each puzzle family (e.g. Pic-a-Pix) has its own homepage containing one or more puzzle types which can be played online or printed out to solve with pencil and paper.
The puzzles can also be saved to your computer.
All these puzzles would be great for the Maths class!
Conceptis Puzzles also have an active and informative forum area with over 100,000 registered users.
Interestingly, Conceptis is the "leading supplier of Sudoku and many more logic puzzle families to printed, electronic and other gaming media all over the world".
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