Polygony
$19.95
Polygony consists of 23 pieces that are rearranged to form four different regular polygons: an equilateral triangle, a square, a hexagon, and an octagon. The pieces are made of magnetic foam so they can either be used on a flat surface or a magnetreceptive vertical surface such as a file cabinet or some white boards. Classroom activities and blackline masters are included, with four activities designed to address specific Common Core State Standards for Mathematics for 8th grade and high school geometry. This fascinating puzzle will challenge the spatial reasoning abilities of even the most gifted students and adults. Ages 12 and up.

KnoTiles
$14.95
Everyone is familiar with the utilitarian and decorative uses of knots, but mathematicians study knots as well. KnoTilesTM is a puzzle that serves as an introduction to the mathematics of knots and the symmetry of knot designs. All of the knots through seven crossings can be formed with the set, and the instructions contain over a dozen brain teasers. The puzzle pieces feature photographic rope images, with a second color of rope on some pieces to allow the formation of links (like knots, but with more than one strand). 105 cardboard pieces. Grades 312.

Four Tricky TwoWay Puzzles
$9.95
Turn a square into a triangle? How is that possible? Each of the four squares in this set can be transformed into a different geometric shape. See how fast you can solve them. Ages 8 to adult.

Four Tricky TwoWay Star Puzzles
$9.95
Even a square can become a star! In this set, four squares are rearranged to form four different star shapes. Ages 8 to adult.

Four Tricky Tangram Puzzles
$9.95
The Tangram is just the beginning! In addition to the ancient Chinese classic, this set includes three other Tangramlike puzzles. A Japanese puzzle that actually predates the tangram by half a century, and two more recent designs. Ages 8 to adult.

Cubed Cubes
$14.95
Cubed Cubes is a brain teaser puzzle that teaches students about rectangular solids and the cubic numbers. The foam pieces form red, blue, and green cubes, each of a different size. In addition, all nine pieces together form a larger cube. The puzzle is based on the mathematical curiosity that the cubes of 3, 4 and 5 sum to the cube of 6. The instructions include several additional threedimensional puzzles to solve using the same pieces. Also included are classroom worksheets on the volume of rectangular solids and cubic numbers. Grades 212.

The Irrational Puzzle
$19.95
This set contains four cubes dissected four different ways to form a variety of geometric solids. The instructions contain seven brain teasers in which different threedimensional geometric shapes are formed with the pieces. This puzzle makes use of the fact that the face diagonal and space diagonal of a unit cube are the squares roots of 2 and 3, respectively, to introduce students to the concept of irrational numbers. Three reproducible worksheets cover the history of the square root of 2, the discovery of irrational numbers, and the Pythagorean Theorem. Contains 11 geometric solids made from soft, durable, and nontoxic foam. Cubes measure 2.5" on a side. Grades 312.

TangraMagic
$4.95
This foam puzzle consists of the ancient Chinese Tangram plus three additional pieces. Remove all the pieces and replace them without the magic square to fill the frame again! Plus fifteen original Tangram paradoxes.
Ages 8 to adult.

Squared Squares
$6.95
Squared Squares contains 48 magnetic foam pieces, each of which is a square. All 48 pieces form a large square, and all of the pieces of each color form different smaller squares. But that's just the beginning; seven more brain teasers will really put you to the test!
