Puzzles, Magic, Problems...
Erich Friedman's web site provides you with a myriad of resources to both challenge and "recreate" your mathematics students. Some of the web site's contents are being reviewed on the Website Page and some on the Humor Page.
First, if you are looking for a puzzle..then Erich's "Puzzle Palace" is a good place to go. Erich offers 55 different types of puzzles, some them published in recreational magazines. Unable to provide a list of all the types, I will list only five examples:
Or, if you are looking for good source of challenging problems..then Erich's "Math Magic" is a good place to go. Erich offers you a monthly problem, plus an Archive containing 10 years of problems. Again, I am unable to provide a list of all of the problems...just go there and you will not only get pleasantly lost (if you enjoy solving problems) but also find some good problems (with solutions and commentary) to push your students to think creatively. Use the links he provides to find other good problem collections.
- Mirror Puzzles
- Diamond Puzzles
- Weight Puzzles
- Distance Puzzles
- Equation Puzzles
Third, if you enjoy geometry challenges, browse through Erich's "Packing Center." To illustrate (or tempt), the first task involves finding the smallest square (of side length s) that can contain a "packing" of n equilateral triangles with side length 1. Erich then offers you 51 variants on this task...but offers no proof as to why his answers are correct.
Finally, if you have time, browse through Erich's "Puzzle Collection." Most of the 967 puzzles are mechanical...and oddly familiar. Unfortunately, one can only look at them, yet playing with them would drive me (or you) crazy!