How to Subitize – See numbers in your head

Easily subitize by breaking numbers into pairs of three. 1,2,3 and 4,5,6 and 7,8,9 can be grouped together.
To subitize is to mentally count individual units of one. A quick way to subitize is to group numbers in three’s.

When I learned math as a child, I went straight to memorizing numerals. What I did not fully understand was what the numerals actually represent. This slowed down my math.

Determined to solve this problem, I figured out a system for counting that groups numbers 1 through 9 into chunks of three. This counting system is pictured above. It almost looks like braille and could be converted into raised bumps for the blind and visually impaired.

This system came to me in February 2016 as I was walking through my neighborhood and trying to count leaves on clovers or petals on flowers. It was hard to arrive at an accurate count after only glancing at the object. In fact, the dictionary definition of Subitize offers that the limit for humans to subitize is seven.

I did notice on my walk that I could accurately count one object. I could count two objects. Counting three objects was also possible. But counting anything beyond three was not accurate unless I slowed down. It was then that the idea came to me to “chunk” what I was seeing into groups of three.

Building on that realization, I formed the subitizing system that is pictured above. In this system, there are three columns and three rows of dots. In column one are numbers 1, 2 and 3; they extend into the first row below. In column two are numbers 4, 5 and 6; they extend into the first and second rows below. In column three are numbers 7, 8 and 9; they extend into the first, second and third rows below.

With this new system of counting, I am now able to study the patterns that exist between numbers 1 through 10, which are accelerating my skills in mental math and finance.

Leave a Reply