Taipei 101 Foundations (multiplication, proof)

Taipei 101 Foundations (multiplication, proof)

Before the wise builder builds – the wise builder thinks. Here we are going to build the foundations of a great skyscraper – Taipei 101. Start with a 6×6 grid. Add numbers or letters or colors to the top left part of the grid as shown. Now is the...
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....
Integral Centrifuge (multiplication of +/-1)

Integral Centrifuge (multiplication of +/-1)

This spinning centrifuge has a matching set of -1 (South) and +1 (North) magnets on the inner and outer ring. The inner ring is the one that spins. You must try to find a combination of +1s and -1s so that when it is rotated away from this all-repulsive position there...
Coup (2-6 players; 15 minutes; ages 9+)

Coup (2-6 players; 15 minutes; ages 9+)

Coup (2-6 players; 15 minutes; ages 9+) Coup is a game of bluff and deception. Without a doubt, it is one of the most popular games I’ve ever introduced to the grade 5-9 classroom. The game is ridiculously fast with two players – maybe 5...