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Mathematics (2019) Grade(s): 1


Use addition and subtraction to solve word problems within 20 by using concrete objects, drawings, and equations with a symbol for the unknown number to represent the problem.

Unpacked Content


Students know:
  • addition and subtraction strategies and models.
  • how to form an equation.


Students are able to:
  • represent quantities and operations (addition & subtraction) with concrete objects, pictorially, or symbolically.
  • Use informal and mathematical language to communicate the representations.
  • Accurately compute sums and differences.


Students understand that:
  • addition is both putting together and adding to. subtraction is taking apart, taking from, and comparisons.
  • Mathematical problems can be solved using a variety of strategies. models, and representations.
  • variables in the form of blanks, boxes, or letters, represent unknown quantities when representing mathematical situations algebraically.


  • Change unknown
  • Put together
  • Take apart
  • Compare