Explaining Addition and Subtraction Strategies
Students explain why addition and subtraction strategies work, using place value and the properties of operations.
Key Questions
- Analyze how the associative property of addition can simplify a problem.
- Explain the connection between counting by tens and adding ten repeatedly.
- Critique a strategy that incorrectly applies place value concepts.
Common Core State Standards
Suggested Methodologies
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Planning templates for Mathematics
5E Model
The 5E Model structures lessons through five phases (Engage, Explore, Explain, Elaborate, and Evaluate), guiding students from curiosity to deep understanding through inquiry-based learning.
unit plannerMath Unit
Plan a multi-week math unit with conceptual coherence: from building number sense and procedural fluency to applying skills in context and developing mathematical reasoning across a connected sequence of lessons.
rubricMath Rubric
Build a math rubric that assesses problem-solving, mathematical reasoning, and communication alongside procedural accuracy, giving students feedback on how they think, not just whether they got the right answer.
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