Mental Addition and Subtraction Strategies
Students develop and apply mental strategies for adding and subtracting 2- and 3-digit numbers, including making tens, compensating, and using known facts.
Key Questions
- How does making a ten or hundred make addition easier?
- What is the compensation strategy, and when is it useful?
- How can we use known addition facts to solve subtraction problems mentally?
MOE Syllabus Outcomes
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.
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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.
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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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