Khan Academy
Khan Academy: Challenge Problems: Circumscribing Shapes
Solve two challenging problems that apply properties of tangents to find the perimeter of a circumscribing shape.
Other
Art of Math: Making Math Fun
This site offers customizable math challenges to help students master their math facts. Options include skill, age, and difficulty level as well as number of problems.
University of Georgia
University of Georgia: Inter Math: Line of Symmetry
This site gives a description of a line of symmetry along with an with a visual representation. There are links to related terms, everyday examples, challenging problems, more information, and the interactive check point involving lines...
National Council of Teachers of Mathematics
The Math Forum: Famous Problems in the History of Mathematics
On this site, there are several math problems to explore and solve. Look through some solutions by famous mathematicians and expand your thinking about some interesting math concepts. Teachers of elementary grades may want to use this...
University of Cambridge
University of Cambridge: Maths and Sports: The Olympic Torch Tour
Can you find the best route for the Olympic Torch relay to take? This more challenging activity is designed to be accessible to GCSE maths students (grades 8, 9, and 10).
Other
Odyssey of the Mind Curriculum Activity: Made Up Math
An interesting way to make math more creative. This page gives ideas for three different exercises that encourage students to use math in a creative way.
University of Georgia
University of Georgia: Inter Math: Dependent Events
This site gives a description of dependent events along with an example. Be sure to follow the links to related terms, everyday examples, challenging problems, more information, and the interactive check point involving dependent events...
University of Georgia
University of Georgia: Inter Math: Interactive Math Dictionary
Each term of Intermath's interactive math dictionary contains a description and links to related terms, everyday examples, interactive checkpoint, more information, and challenges located in the left-hand column of the page. This...
National Council of Teachers of Mathematics
Nctm: Figure This: Is There Room for All These Gifts?
This math challenge activity focuses on the concept of organizing information. Test your problem-solving aptitude as you try to figure out who received the most gifts.
National Council of Teachers of Mathematics
Nctm: Figure This: Can You Turn a Frown Into a Smile?
This math challenge activity focuses on the concept of morphing. Test your problem-solving aptitude as you try to morph a frown into a smile.
Oswego City School District
Regents Prep: Applications of Trigonometric Graphs
Students can use this site to practice questions dealing with trigonometric graphs. Students are challenged with multiple real-world problems and after solving those problems they can check their solution online.