Mathschallenge.net. To use the search facility enter your keywords, separated by spaces, in the box below. The engine will scan through the problem description, details, solution, and a set of topic keywords for every problem. You can further refine your search by requiring an exact match of every word in your list (AND) or any of your keywords (OR). You can also select the difficulty level of the problem, for which guidance is given below. Guidelines to level of difficulty: These problems require nothing more than a logical mind and a willingness to try things out on paper. Problems begin to require insights and mathematical tools. A good knowledge of school mathematics and/or some aspects of proof will be required. A comprehensive knowledge of school mathematics and advanced mathematical tools will be required. Please note on many problems that, although they start at a particular level of difficulty, the extensions may extend it considerably beyond its initial level of difficulty.
Graphing Stories - 15 seconds at a time. Math Mistakes « Would You Rather? | Asking students to choose their own path and justify it. Visualpatterns. Estimation 180 - Home. 101questions. Starter Of The Day. Puzzle! Slitherlink, Nurikabe, Heyawake, Sudoku... - run by Nikoli [www.nikoli.com]