Three Color Equilateral Triangle

Three Color Equilateral Triangle

Find a coloring of these vertices so that no equilateral triangle can be found that has all three corners the same color. Here we failed because the highlighted triangle has three red corners. It also fails because this highlighted triangle has all its corners yellow....
Armenian Rug Puzzles (logic)

Armenian Rug Puzzles (logic)

Armenian rugs cover the floor – sometimes laying atop each other. A whole lot of puzzles arise from trying to find the shape and placement of these rugs. PS. The photo is of the oldest pile rug to be discovered – 2500 years old. It is Armenian, but was...
Picasso’s Cuboids (volume puzzle)

Picasso’s Cuboids (volume puzzle)

Picasso’s cuboid puzzle uses volume in an unequal battle between a Greedy and Generous Cuboid. 20 can be written as the sum of the volumes of two cuboids… a Greedy one and a Generous one… All three dimensions of the Greedy Cuboid {3,3,2} are at least as...
Pinocchio’s Playmates (pattern puzzle)

Pinocchio’s Playmates (pattern puzzle)

The Adventures of Pinocchio were written by Carlo Collodi in 1883. This puzzle was inspired by imagining Pinocchio’s classroom – full of little people who always lied or always told the truth. In one of his classroom the truth teller students and liar...
ConHex (strategy game)

ConHex (strategy game)

ConHex (Michail Antonow, 2002) ConHex is a pencil and paper game curricular for students learning about perimeter, but the most important reason to play any game like this is to get students thinking rigorously as they try to beat one another. As with most connection...