Mathematics · Class 2

Active learning ideas

Regrouping Concepts in Subtraction

Active learning works well for regrouping in subtraction because students need to physically experience the exchange of tens and ones to understand how place value changes. Concrete manipulatives help students grasp abstract concepts by making the borrowing process visible and tactile, reducing confusion between procedural steps and conceptual understanding.

• CBSE Learning Outcomes
• CBSE: Addition and Subtraction with Regrouping - Class 2

• 20–45 min
• Pairs → Whole Class
• 4 activities

Activity 01

• Experiential Learning
• 30 min · Pairs

Manipulative Exchange: Base-10 Blocks Subtraction

Provide base-10 blocks for numbers like 32 and 15. Students build both numbers, then exchange a ten rod for ten unit blocks when ones are insufficient, subtract, and record steps. Discuss how the total value stays the same before and after regrouping.

What is actually happening to the value of a number when we borrow a ten?

Facilitation Tip

During the Manipulative Exchange activity, circulate and ask guiding questions like, 'Show me how the total value stays the same after you exchange one ten for ten ones.'

What to look for

Present students with the problem: 41 - 23. Ask them to use base-10 blocks or draw tens and ones to show how they would regroup the tens to solve this problem. Observe if they correctly exchange one ten for ten ones.

• Apply
• Analyze
• Evaluate
• Self-Awareness
• Self-Management
• Social Awareness

Activity 02

• Experiential Learning
• 45 min · Small Groups

Story Problem Stations: Regrouping Scenarios

Set up three stations with story cards needing regrouping, like '32 mangoes minus 15 eaten'. At each, students use counters to act out borrowing, draw representations, and solve. Rotate groups every 10 minutes and share one solution as a class.

Justify why we need to 'borrow' from the tens place when we don't have enough ones to subtract.

Facilitation Tip

In the Story Problem Stations, encourage students to act out the scenarios with base-10 blocks to reinforce the real-world context of regrouping.

What to look for

Give each student a card with a subtraction problem requiring regrouping, such as 53 - 18. Ask them to write one sentence explaining why they needed to regroup and then solve the problem. Collect these to check understanding of the concept and calculation.

• Apply
• Analyze
• Evaluate
• Self-Awareness
• Self-Management
• Social Awareness

Activity 03

• Experiential Learning
• 20 min · Pairs

Visual Draw-Along: Regrouping Diagrams

Display 32 - 15 on the board. Students draw tens and ones sticks, cross out for regrouping, then subtract. Pair up to check drawings match the answer 17 and explain the exchange.

Construct a visual representation of subtracting 15 from 32 using regrouping.

Facilitation Tip

For the Visual Draw-Along activity, model the first problem step-by-step on the board, narrating your thoughts aloud to make the process explicit.

What to look for

Pose the question: 'Imagine you have 3 tens and 2 ones, and you need to subtract 5 ones. What must you do first, and why?' Facilitate a class discussion where students explain the need for regrouping and the value exchange.

• Apply
• Analyze
• Evaluate
• Self-Awareness
• Self-Management
• Social Awareness

Activity 04

• Experiential Learning
• 35 min · Pairs

Regrouping Relay: Number Cards

Place subtraction cards around the room requiring regrouping. Pairs race to solve one using mini-manipulatives, tag the next pair. Debrief whole class on common borrowing steps.

What is actually happening to the value of a number when we borrow a ten?

Facilitation Tip

In the Regrouping Relay, pair students heterogeneously so peers can support each other’s understanding during the quick-paced card activity.

What to look for

Present students with the problem: 41 - 23. Ask them to use base-10 blocks or draw tens and ones to show how they would regroup the tens to solve this problem. Observe if they correctly exchange one ten for ten ones.

• Apply
• Analyze
• Evaluate
• Self-Awareness
• Self-Management
• Social Awareness

A few notes on teaching this unit

Start with concrete manipulatives before moving to visual representations and then abstract symbols. Research shows that students learn regrouping best when they first work with physical objects like base-10 blocks, then draw diagrams to represent exchanges, and finally solve problems on paper. Avoid rushing to the algorithm; instead, build procedural fluency from conceptual understanding. Use consistent language like 'exchange one ten for ten ones' to avoid confusion between terms like 'borrow' or 'carry' which may differ across regional contexts.

Successful learning is evident when students confidently explain why regrouping is necessary, use manipulatives or diagrams to model exchanges, and apply the process accurately in subtraction problems. Students should also articulate the relationship between place values during exchanges and demonstrate this understanding in peer discussions.

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Watch Out for These Misconceptions

• During the Manipulative Exchange activity, watch for students who believe exchanging a ten rod for ten unit blocks reduces the total value of the number.

  Have students recount the total number of blocks before and after the exchange to see that the value remains the same. Ask them to explain why the total hasn’t changed, reinforcing the concept of place value and conservation of quantity.

• During the Story Problem Stations activity, observe if students attempt to subtract a larger digit from zero without regrouping.

  Prompt them to model the problem with base-10 blocks and discuss why zero ones cannot subtract a larger number without borrowing from the tens place first.

• During the Visual Draw-Along activity, note if students treat the tens and ones places as separate, unrelated numbers.

  Ask them to draw arrows or write notes connecting the exchanged ten to the ones place, showing how the groups interact to maintain the number’s value.

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Methods used in this brief

• Experiential Learning