Maths Challenge
Maths challenge.net: Problem Solving Database
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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Teach Net: Brain Binders
Brain binders are great teacher sources for problem solving and critical thinking with geometry. Students fold sheets of paper to create solid colors on each side. Various levels are included starting with two folds through five folds.