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Mathematics (2019) Grade(s): KG


Compose and decompose numbers from 11 to 19 by using concrete objects or drawings to demonstrate understanding that these numbers are composed of ten ones and one, two, three, four, five, six, seven, eight, or nine ones.

Unpacked Content


Students know:
  • the number sequence to 19.
  • Strategies to decompose a number into tens and ones.


Students are able to:
  • Use objects to compose and decompose numbers.


Students understand that:
  • ten things can be represented as one ten or as ten ones.


  • Compose
  • Decompose