Adding Two-Digit Numbers (With Regrouping)
Students add two two-digit numbers with regrouping, understanding the concept of composing a new ten.
Key Questions
- Justify why we 'carry over' a ten when the sum of the ones is 10 or more.
- Construct a model to show how 10 ones become 1 ten during addition.
- Critique a common error made when regrouping in addition.
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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