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Maths Challenge

Maths challenge.net: Problem Solving Database

For Teachers 9th - 10th Standards
Need some challenging problem-solving work for your students in the following areas: Discrete, Geometry, Numbers, and Code Breaking? This is the place for an enormous database of problems aimed at high school age students. They are...
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Brain Food: Puzzles for the Brain to Gnaw On

For Students 9th - 10th
This site includes many games and puzzles ranging from word games to logic problems to riddles. These puzzles can be completed on line and offer interactive hints and solutions.
Activity
Cut the Knot

Cut the Knot: Eight Digits Puzzle

For Students 9th - 10th
Challenge yourself to this tricky little puzzle in which the player must position 8 digits in a pattern without having any paths connecting successive digits.
Interactive
Math Is Fun

Math Is Fun: Math and Logic Puzzles

For Students Pre-K - 1st
A collection of puzzles that will challenge your knowledge of measurement, logic, symmetry, numbers, algebra, and other math-related topics.
Interactive
ABCya

Ab Cya: Math Puzzle: Sudoku

For Students 3rd - 5th
Plug in numbers to complete the equations and solve Sudoku puzzles.
Professional Doc
Discovery Education

Discovery Education: Puzzlemaker

For Teachers 9th - 10th
At this site create your own puzzles, build your own maze and print them out for yourself or others to enjoy.
Activity
National Institute of Educational Technologies and Teacher Training (Spain)

Ministerio De Educacion: Geo Gebra Prim (Conexiones Misteriosas)

For Students 3rd - 8th
Challenge yourself with this puzzle. Try to connect the dots of the same color with horizontal and vertical segments without leaving the grid and without crossing the lines.
Activity
Ministry of Education and Employment of Spain

Red Escolar: Problemas De Holmes 2002

For Students 3rd - 5th
In Spanish. Practice your mental math skills with this site. You will find different activities for every month of the year. Different levels of difficulty and suggested time limit for each activity are also provided.
Activity
National Council of Teachers of Mathematics

The Math Forum: Increasing Wall Area

For Students 9th - 10th
This site presents a problem at a museum that has one large square gallery. The director wants to divide this room down the middle into four smaller square rooms.
Activity
Mensa Espana

Mensa: Juegos De Ingenio Del Club Mensa (001 005)

For Students 9th - 10th
Challenge yourself with these five math problems. Each problem is marked by their levels of difficulty.
Activity
Mensa Espana

Mensa: Juegos De Ingenio Del Club Mensa (011 015)

For Students 9th - 10th
Challenge yourself with these five math problems. Each problem is marked according to their levels of difficulty.
Activity
Mensa Espana

Mensa: Juegos De Ingenio Del Club Mensa (016 020)

For Students 9th - 10th
Challenge yourself with these five math problems. Each problem is marked according to their levels of difficulty.
Activity
Mensa Espana

Mensa: Juegos De Ingenio Del Club Mensa (006 010)

For Students 9th - 10th
Challenge yourself with these five math problems. Each problem is marked according to their levels of difficulty.
Activity
Mensa Espana

Mensa: Juegos De Ingenio Del Club Mensa (021 025)

For Students 9th - 10th
Challenge yourself with these five math problems. Each problem is marked according to their levels of difficulty.
Activity
Mensa Espana

Mensa: Juegos De Ingenio Del Club Mensa (026 030)

For Students 9th - 10th
These math problems can help to prepare you for future math competitions. Each problem is marked according to their levels of difficulty.
Activity
Mensa Espana

Mensa: Juegos De Ingenio Del Club Mensa (031 035)

For Students 9th - 10th
These math problems can help to prepare you for future math competitions. Each problem is marked according to their levels of difficulty.
Activity
Mensa Espana

Mensa: Juegos De Ingenio Del Club Mensa (036 040)

For Students 9th - 10th
These math problems can help to prepare you for future math competitions. Each problem is marked according to their levels of difficulty.
Activity
Mensa Espana

Mensa: Juegos De Ingenio Del Club Mensa (041 045)

For Students 9th - 10th
These math problems can help to prepare you for future math competitions. Each problem is marked according to their levels of difficulty.
Activity
Mensa Espana

Mensa: Juegos De Ingenio Del Club Mensa (046 050)

For Students 9th - 10th
These math problems can help to prepare you for future math competitions. Each problem is marked according to their levels of difficulty.
Activity
Mensa Espana

Juegos De Ingenio Del Club Mensa (051 055)

For Students 9th - 10th
Solve these math problems to practice for future math competitions. Each problem is marked according to their levels of difficulty.
Activity
Mensa Espana

Mensa: Juegos De Ingenio Del Club Mensa (056 060)

For Students 9th - 10th
Solve these math problems to practice for future math competitions. Each problem is marked according to their levels of difficulty.
Activity
Mensa Espana

Mensa: Juegos De Ingenio Del Club Mensa (061 065)

For Students 9th - 10th
Solve these math problems to practice for future math competitions. Each problem is marked according to their levels of difficulty.
Activity
Mensa Espana

Mensa: Juegos De Ingenio Del Club Mensa (066 070)

For Students 9th - 10th
Get ready for future math competitions with these five math problems. Each problem is marked according to their levels of difficulty.
Activity
Mensa Espana

Mensa: Juegos De Ingenio Del Club Mensa (071 075)

For Students 9th - 10th
Get ready for future math competitions with these five math problems. Each problem is marked according to their levels of difficulty.