Decanomial Square

July 11, 2017
The decanomial square is one of the most visually appealing materials in the entire Montessori classroom.

The main purpose of the activity is to help children learn how to discriminate size, shape and color. It is also preparation for math, with squaring.

Here’s how it works:

The materials come neatly organized in a wooden box.

One of Montessori’s fundamental ideas was that children should be enticed by the work, that the materials should seduce them to want to engage.

The decanomial square is no exception. As a matter of fact, it might be the rule.

There are exactly 10 squares. These squares increase in size, starting from 1cm x 1cm to reaching 10cm x 10cm. Each square has a corresponding rectangle, except for the very first square, the red one – as shown here.

To get started, a child will place the red square in the top left corner of the floor mat. From there, they will place the green square on the diagonal, like so, adding the green rectangles as they proceed, completing the square.

Continuing on, the child will place the next largest square in the box along the diagonal, following the logic above, until they have completed the entire activity.

One of the indirect lessons of the activity is establishing visual harmony. A child can also easily recognize when a pattern is out of place, thus utilizing the famous Montessori control of error method.

Receive our Newsletter

We send out infrequent dispatches with fun bits and useful information to our subscribers.

Become a Contributor

Have an idea? Want to contribute? Join us and help grow our community of learners. Send us an email and we'll be in touch shortly!

Contact Support

Please fill out the entire form below and a support team member will contact you shortly.
  • Be the first to receive our newsletter, fresh off the presses, complete with inspirational content and special, behind the scenes access.