Adding and Subtracting within 200
Students will add and subtract numbers within 1000 using concrete models or drawings and strategies based on place value.
Key Questions
- How are the steps for adding three-digit numbers similar to adding two-digit numbers?
- Can you use an open number line to solve 126 + 45?
- What strategy would you use to solve 183 − 50?
Ontario Curriculum Expectations
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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