Students explore and apply the associative and commutative properties of addition within the context of finding the volume of buildings built from connecting cubes. Students then apply these properties to solve multistep problems involving addition.

EXPECTATIONS
	Use this list of Expectations to assess students on the key concepts and skills in this unit.
E1*	Recognize that different partitions of a number have the same total (e.g., 50 + 4 = 40 + 14).
E2	Solve problems (e.g., part-whole, join) involving volume.
E3*	Apply the properties of addition (e.g., commutative, associative) to write number sentences that represent the volume of a building.
E4	Make connections between a building of cubes, the building plan, and number sentences.
E5	Identify shapes that are the same size and shape.
E6	Recognize that different shapes can have the same volume.
E7	Identify and measure the dimensions (floor plan, height) of a building.
E8	Count and add cubic units to find volume.
E9	Construct a building plan given the volume (number of cubes), floor plan, and height.
E10*	Demonstrate fluency with the subtraction facts related to the addition facts in Group B (3 − 0, 4 − 0, 5 − 1, 5 − 4, 6 − 1, 6 − 5, 7 − 1, 7 − 2, 7 − 5, 7 − 6, 8 − 1, 8 − 2, 8 − 3, 8 − 5, 8 − 6, 8 − 7, 9 − 1, 9 − 8).
E11*	Determine the unknown number in an addition or subtraction sentence relating three whole numbers for the facts in Group B.
	* Denotes Benchmark Expectation