## Saturday, 30 November 2013

### Montessori Activity: Constructive Triangles - Rectangular Box

Age: From 4 years old

Objectives:

1. To show different triangles can be used to make different shapes.

2. To prepare the child for geometry.

Materials:

1. The Montessori Rectangular Box
2. 1 mat

Directions:

1. Show where the rectangular box is kept and bring it to the mat.

2. Take all triangles out and spread them out randomly on the mat.

3. Show the child the gray triangle, let him feel it and say, "this is equilateral triangle.

4. Tell the child that "I am going to build different shapes with the triangle."

5. Take out 1 green triangle put it in front of you.

6. Take out the other green triangle and slide it into the previous one by matching the black line together to form a square.

7. Match the two yellow equilateral triangles by the black lines to form a rhombus (i.e. a quadrilateral all of whose sides have the same length) (菱形).

8. Match the two gray isosceles triangles (i.e. 2 equal sides triangles) (等腰三角形) by the black lines to form a rectangle.

9. Match the two yellow scalene right-angle triangles (i.e. triangle with no 2 sides of equal length) (不等边三角形) by the black line to form a parallelogram (平行四边形).

10. Repeat for all the remaining pairs of triangles to form different shapes e.g. the different parallelograms and a trapezoid (梯形) etc.

11. Mix all the triangles up again and encourage the child do it.

12. Show the child how to place the triangles back into the box in the correct order: red triangles, yellow triangles, green triangles and the gray triangle.

Video Demonstration:

Control of Error:

The black lines

Language:

If the child shows interest, name the shape formed: square, rectangle, parallelogram, rhombus and trapezoid.

References:

Basic Montessori Learning Activities for Under-Fives by David Gettman
http://faculty.fullerton.edu/syen/mts/sensor/13.htm
http://www.infomontessori.com/sensorial/visual-sense-constructive-triangles-rectangular-triangles.htm

You can find the Montessori rectangular box from amazon: