Subitizing is quickly recognizing and naming the number in a group without counting. “Subitize” comes from the Latin “to arrive suddenly.”

It begins in infancy with a sensitivity to number. Then children learn to recognize very small numbers. Later, they learn to do it quickly-- perceptual subitizing. Another qualitative progression is their ability to see several groups and combine them quickly into one quantity - conceptual subitizing.

Practice-based Research: Children who can quickly recognize numbers, taking a mental “snapshot” of them, without counting, are more able to determine the number of items in a collection, represent that number, and, later, add the numbers.

The word numerals means “written numbers,” such as 1 and 4. These symbols can also be written as number words (one and four). An actual number is the idea of, for example, four things. We might use the word numerals when reading or writing them, but we do not insist that children do so. Also, using numerals to label numbers, as well as representing collections with written symbols, are key steps toward mathematical abstraction. So, they are used in many activities (often linked to verbal number words or dot patterns).

Inclusive Teaching Approaches

We are working with our partners at the STEM Innovation for Inclusion in Early Education (STEMI2E2) Center  to improve engagement opportunities for young children with disabilities (O-5). 

Accessibility for Diverse Educators 

  • Almost all of the videos on our website have closed captions in English and Spanish for the deaf and hard of hearing.
  • Most of our videos can also be accessed with a voiceover describing the scene for those with vision impairments. Click on the Accessibility toggle in the bottom right corner.

Accessibility for Children 

Learn how to incorperate Subitizing across the whole day in Routines, and find accomodations for diverse learners in all levels of Subitizing in Teaching Strategies. 

We have also created new activities or updated previous activities with new features that support engagement for all children. Features of the activities include intentionally inclusive design, accommodations for specific disabilities, questions for caregiver and early interventionist reflection on development, and ideas for learning in everyday routines. We have started by developing activities for infants and toddlers, with plans to add more at the older levels in the future. New inclusive activities for Counting are linked below (and also embedded in the site, at their respective trajectory level).

Levels: Number Senser Foundations and Very Small Number Recognizer

Level: Maker of Small Collections

General accommodation recommendations can be accessed in our Inclusion resources, linked here.  

Read more about the STEMIIEE center here at their website

Special Thanks To

Institute of Education Sciences
The research reported here was supported by the Institute of Education Sciences, U.S. Department of Education, through grant numbers R305K050157, R305A120813, R305A110188, and R305A150243. to the University of Denver. The opinions expressed are those of the authors and do not represent views of the Institute or the U.S. Department of Education.