## Saturday 30 November 2013

### Montessori Activity: Constructive Triangles - Blue Rectangular Box

Age: From 4 years old

Objectives:
1. To construct all possible shapes by sliding and flipping only 2 triangles.

2. To prepare the child for geometry.

Materials:
1. The Montessori Blue Rectangular Box
2. 1 mat

Directions:
1. Show where the blue rectangular box is kept and bring it to the mat.
2. Take 2 triangles out and make a shape, saying "Let's make a shape using these 2 triangles."
3. Slide 1 triangle against the edges of the other and see the shapes formed.
4. Name the shapes created one by one.
5. Encourage your child to try.

Variations:
1. Flipping over one of the pairs to make new shapes.

Video Demonstration:

Language:
If the child shows interest, name the shape formed: square, rectangle, parallelogram, rhombus (4 equal lengths) and trapezoid.

J tried this for the first time on 8 Dec. 2013 (4Y9M3D). He refused to slide the triangles, preferrbly to make his own shapes and patterns with them. Arrgghhh... some days are like that!

References:
Basic Montessori Learning Activities for Under-Fives by David Gettman
http://faculty.fullerton.edu/syen/mts/sensor/16.htm
http://www.infomontessori.com/sensorial/visual-sense-constructive-triangles-blue-rectangular-box.htm
http://www.mathsisfun.com/definitions/rhombus.html
http://www.mathsisfun.com/definitions/trapezoid.html

You can find the Montessori rectangular box from amazon:

 8 Dec. 2013 (4Y9M3D) - J made a person with the triangle - head, upper body, lower body and two triangles as legs

 J refused to slide the triangles to make different shapes, preferring to play with it his own way