Visualizing Numbers

"1,2,3, Look at me.  Tell me the number that you see."

This was today's refrain as we worked on Quick Images.  The Investigations curriculum makes extensive use of this type of activity.  Students are briefly shown an arrangement of dots, and they are asked to quickly determine how many dots they were shown.  They are not given enough time to count the dots one by one and so they must adopt other strategies, combining small groups, etc., to determine the amount.  These activities are supposed to recur regularly throughout the school year with dot arrangements that become more complicated over time. 
 
I have sometimes wondered about the usefulness of this activity.  It isn't an activity that occurs in traditional math curriculums, and I didn't spy anything in the common core standards about visualizing numbers.  Then I read Subitizing: What Is It? Why Teach It? by Douglas H. Clements which details the various theories and research supporting Quick Images activities and makes a convincing case for providing regular opportunities for students to practice recognizing and visualizing number groups.  It would seem that recognizing number groups is a skill underlying many of the skills required in the common core. 
 
There are a few suggestions that Clements makes that I'd like to work on applying in the classroom.  The first is to include quick recognition of auditory or kinesthetic numbers... how many taps?  how many dings?  The second is to work on recognizing numbers in different formats like the "Tens Frame."  I've been using the tens frame pretty extensively since it is prominently featured in the Scott Foresman curriculum, but today I introduced it to students for the first time using Quick Images. 
 
I worked with small groups at the round table on quick images-- youngers were identifying numbers on a tens frame; olders were identifying addition sums on a tens frame.  Meanwhile a new math choice activity was working with dominoes, matching numbers to create a domino path.