Addition Strategies: Making Ten and Doubles
Students will practice mental math strategies like making ten and using doubles to solve addition problems within 20.
Key Questions
- Analyze how 'making ten' simplifies addition problems.
- Compare the efficiency of using doubles versus counting on for certain sums.
- Explain why knowing 6+6 helps you solve 6+7.
Ontario Curriculum Expectations
About This Topic
States of Matter introduces students to the observable properties of solids and liquids. In the Ontario Grade 2 curriculum, students learn to distinguish between these states by exploring how they occupy space and behave when moved or poured. This unit encourages students to use their senses to describe textures, shapes, and the way materials flow. It also touches on the safety aspects of handling different substances, which is a key life skill.
Students investigate why some solids, like sand, can seem to act like liquids, and why liquids always take the shape of their container. This topic is perfectly suited for station rotations and hands-on testing. When students can physically manipulate materials, stacking blocks versus pouring water, they build a concrete understanding of physical properties. Active exploration allows them to test their own hypotheses about how matter behaves in the real world.
Active Learning Ideas
Stations Rotation: The Property Lab
Set up stations with different materials (sponge, water, rock, oil, sand). Students rotate through, performing tests like 'Can I stack it?' or 'Does it change shape in a bowl?' and recording their findings in a simple chart.
Think-Pair-Share: The Sand Mystery
Show students a jar of sand being poured. Ask: 'Is this a liquid or a solid?' Students think individually, pair up to discuss based on their observations of individual grains, and then share their conclusion with the class.
Inquiry Circle: Liquid Races
In small groups, students predict which liquid (water, maple syrup, or dish soap) will flow down a tilted tray the fastest. They conduct the race, measure the results, and discuss how 'thickness' or viscosity changes a liquid's behavior.
Watch Out for These Misconceptions
Common MisconceptionPowders and sand are liquids because they can be poured.
What to Teach Instead
Students often confuse the behavior of a bulk material with its state. Use magnifying glasses so students can see that sand is made of tiny, hard solids that don't change shape themselves, unlike water droplets.
Common MisconceptionLiquids always stay the same volume.
What to Teach Instead
While true, students often think a tall, skinny glass holds more than a short, wide one. Use a 'conservation of volume' demonstration where students pour the same amount of liquid into different shaped containers to see it is still the same amount.
Suggested Methodologies
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Frequently Asked Questions
What safety symbols should Grade 2 students know?
How do I explain 'gas' to Grade 2s if the unit focuses on solids and liquids?
What are the best hands-on strategies for teaching states of matter?
Why does maple syrup flow differently than water?
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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