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Mathematics (2019) Grade(s): 3


Determine and justify solutions for two-step word problems using the four operations and write an equation with a letter standing for the unknown quantity. Determine reasonableness of answers using number sense, context, mental computation, and estimation strategies including rounding.

Unpacked Content


Students know:
  • Characteristics of addition, subtraction, multiplication, and division.
  • Strategies for addition, subtraction, multiplication, and division.
  • Strategies for mental computation and estimating sums, differences, products, and quotients.


Students are able to:
  • Use a variety of strategies to solve two-step word problems involving all four operations.
  • Write an equation to represent the problem context, and use a symbol for the unknown quantity.
  • Justify strategy and solutions using mathematical vocabulary.
  • Determine and justify reasonableness of solutions using mental computation strategies and estimation strategies.


Students understand that:
  • Mathematical problems can be solved using a variety of strategies, models, and representations.
  • Contextual situations represented by multiplication and division.
  • Reasonableness of solutions can be evaluated by using estimation strategies.


  • Unknown quantity
  • Mental computation
  • Estimation
  • Variable
  • Reasonableness
  • Rounding
  • Expression
  • Equation