Grade 2 · Operations & Arithmetic
Subtract Within 100
Learn to find what remains or how two quantities differ through clear explanations, worked examples, an interactive model, and guided practice.
Lesson coverage
Learn the whole topic, not just one problem type.
This lesson and its practice bank deliberately rotate across these core facets so students build a connected understanding of the subject.
Subtract accurately using efficient strategies.
Find an unknown part, starting amount, or difference.
Connect subtraction to objects, equations, and number lines.
Recognize take-away and comparison situations.
Estimate, compare, and use addition to check.
Build the idea
Subtract Within 100 is part of the build fluency with place value and operations while introducing money, measurement, graphs, arrays, and equal groups. Start by identifying what each quantity, symbol, diagram, or graph represents before calculating.
Fluency
Subtract accurately using efficient strategies. Use a representation that fits the idea, connect it to the relevant mathematical relationship, and explain how the representation supports the result.
Missing values
Find an unknown part, starting amount, or difference. Use a representation that fits the idea, connect it to the relevant mathematical relationship, and explain how the representation supports the result.
Representation
Connect subtraction to objects, equations, and number lines. Use a representation that fits the idea, connect it to the relevant mathematical relationship, and explain how the representation supports the result.
Word problems
Recognize take-away and comparison situations. Use a representation that fits the idea, connect it to the relevant mathematical relationship, and explain how the representation supports the result.
Reasoning
Estimate, compare, and use addition to check. Use a representation that fits the idea, connect it to the relevant mathematical relationship, and explain how the representation supports the result.
Use a reliable strategy
Identify the quantities, choose the operation that matches the situation, calculate carefully, and check whether the result is reasonable.
Check and explain
A correct answer is only part of mathematical understanding. Check units, signs, scale, and whether the result makes sense. Then explain the relationship in words so you can recognize the same structure when the numbers or context change.
Key terms
Words to know
- Subtract Within 100
- The central skill or relationship explored in this lesson.
- Difference
- The result of subtraction.
- Subtract
- To take away or compare quantities.
- Equation
- A statement that two expressions are equal.
Interactive math lab · ⭐ stars
Change it. See it. Understand it.
Change the starting amount and the amount removed.
| Start | 8 |
|---|---|
| Take away | 3 |
| Remaining | 5 |
Worked examples
See the idea in action.
The starting amount is difference + amount removed: 7 + 2 = 9.
Moving left represents subtraction: 14 − 5 = 9.
Guided practice
20 questions drawn from a 150-question lesson bank.
Each practice session mixes the major skills in this lesson so you practice the whole topic, not just one repeated problem type.
What is 12 − 7?
Curriculum reference
Built as a continuous K–12 progression.
The sequence follows widely used K–12 mathematics progressions and references the Common Core mathematics framework. Explanations, examples, interactive models, and practice questions are original FreeLearnHub material.