The purpose of this lesson is for students to add and subtract within 1,000,000 with multiple compositions or decompositions.
In this lesson, students use the standard algorithm for addition and subtraction to the hundred-thousands place. They build their fluency with the algorithm as they encounter examples where more than one digit has to be decomposed in order to subtract. Students also look at errors that are commonly made when using the algorithm to find sums and differences.
- Action and Expression
Activity 1: Add and Subtract Large Numbers
- Add and subtract multi-digit numbers, with multiple compositions or decompositions, using the standard algorithm.
Let’s use the standard algorithm to add and subtract.
Materials to Gather
|Activity 1||15 min|
|Activity 2||20 min|
|Lesson Synthesis||10 min|
Teacher Reflection Questions
What connections did students make between the decomposition of base-ten units using expanded form and using the standard algorithm when subtracting large numbers?
- Tic Tac Round (3–5), Stage 2: Any Place (Addressing)
- Number Puzzles: Addition and Subtraction (1–4), Stage 6: Beyond 1,000 (Addressing)
Print Formatted Materials
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