A pinboard by
Diane P Proctor

I am a teacher of K-12 students with language-based learning disabilities. I love learning.


Subitizing is the ability to 'see' an amount of objects and know how many there are without counting

Subitizing is the rapid, accurate, and confident judgments of numbers performed for small numbers of items. Young children spontaneously use the ability to recognize and discriminate small numbers of objects. But some elementary school children cannot immediately name the number of pips showing on dice. Why does this happen? When and how does it develop? Is it a special way of counting? Should we teach it?

Subitizing: What is it? Why teach it?

Freeman {Freeman, Frank N. "Grouped Objects as a Concrete Basis for the Number Idea."} suggested that whereas measurement focused on the whole and counting focused on the unit, only subitizing focused on both the whole and the unit; therefore, subitizing underlay number ideas. Carper (1942) agreed that subitizing was more accurate than counting and more effective in abstract situations.

In the second half of the century, educators developed several models of subitizing and counting. They based some models on the same notion that subitizing was a more "basic" skill than counting (Klahr and Wallace 1976; Schaeffer, Eggleston, and Scott 1974). One reason was that children can subitize directly through interactions with the environment, without social interactions. Supporting this position, Fitzhugh (1978) found that some children could subitize sets of one or two but were not able to count them. None of these very young children, however, was able to count any sets that he or she...