Students use a variety of strategies to solve subtraction problems using a variety of methods and representations. Students apply place-value properties and use mental math strategies to calculate and estimate differences. Students also learn to use paper-and-pencil strategies (e.g., standard algorithm, expanded form) that apply place value concepts to solve subtraction problems.

EXPECTATIONS
	Use this list of Expectations to assess students on the key concepts and skills in this unit.
E1*	Use and apply place value concepts to make connections among representations of numbers to the thousands using base-ten pieces, number lines, expanded form, and standard form.
E2*	Represent subtraction problems using base-ten pieces and number lines.
E3*	Subtract multidigit numbers using mental math strategies (e.g., composing and decomposing numbers, counting up) with number lines, a 200 Chart, and base-ten pieces.
E4*	Subtract multidigit numbers using paper-and-pencil methods (e.g., expanded form, compact).
E5	Estimate differences using mental math strategies (e.g., rounding using benchmarks, using friendly numbers, composing and decomposing numbers, counting on).
E6*	Demonstrate fluency with the subtraction facts related to the addition facts in Group A (1 − 0, 1 − 1, 2 − 0, 2 − 1, 2 − 2, 3 − 1, 3 − 2, 4 − 1, 4 − 2, 4 − 3, 5 − 2, 5 − 3, 6 − 2, 6 − 4).
E7*	Determine the unknown number in an addition or subtraction sentence relating three whole numbers for the facts in Group A.
	* Denotes Benchmark Expectation