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Alignments to Content Standards: K.OA.A.2


Show the student 6 counters (small, flat objects). Ask the student to close his/her eyes. Hide some of the counters under a sheet of heavy paper. When the student opens his/her eyes, s/he determines how many were hidden based on the number of counters still showing.

IM Commentary

  • Repeat the task 4-5 times per student.
  • This task may be repeated with a different number of counters.
  • Students should eventually be able to recognize the number of counters that are showing and/or hidden without counting.

The words compose and decompose are used to describe actions that young students learn as they acquire knowledge of small numbers by putting them together and taking them apart. This understanding is a bridge between counting and knowing number combinations. It is how instant recognition of small numbers develops and leads naturally to later understanding of fact families.


Students should look at how many counters are showing and determine how many objects are hidden.