# Tangram

*Material Required**: Card paper.*

A tangram set has seven pieces which are obtained from a square. Tangram puzzles were first developed by Chinese over a thousand years ago. Tangram is excellent for children to work for developing concepts of geometric relations.

Procedure: To make the tangram, cut a square piece of card paper. Cut it in smaller pieces (see the picture in appendix). The tangram pieces can be arranged to form hundreds of different shape. Tangrams can also be used to study geometric shapes.

Activities: Once tangram is made, following activities could be done with it

- List the different kinds of figures present in the tangram. How many pairs of equilateral triangles are there in the set? How many squares? etc.
- What is the area of each tangram piece and of the whole tangram set, if the area of the smallest triangle is one unit?

- Make a square, a triangle and a parallelogram using two small triangles and a medium sized triangle.

- Make a rectangle and a trapezium using two small triangles and a parallelogram.
- Make a rectangle, a trapezium and a parallelogram using two small triangles and a square.

- Make a square, a triangle and a parallelogram using two small triangles, one medium sized triangle and a big triangle.

- Make a square, rectangle and a triangle using all seven pieces.
- What is the perimeter of this large square, if the side of the smallest triangle is one unit.

- Can we prove theorems such as the midpoint theorem, properties of a parallelogram using tangram? How?