Mathematics · Primary 1

Active learning ideas

Addition with Regrouping (within 100)

Active learning turns abstract regrouping into a concrete experience that sticks. When students physically exchange 10 ones for a ten using blocks or counters, they see the total stay the same even as the form changes. This hands-on practice builds the mental images needed for mental math later.

• MOE Syllabus Outcomes
• MOE: N(v).5
• MOE: N(v).6

• 25–45 min
• Pairs → Whole Class
• 4 activities

Activity 01

• Experiential Learning
• 35 min · Pairs

Manipulative Sort: Base-10 Regrouping

Provide base-10 blocks and number cards like 28 + 37. Students build each number, add ones, then regroup 10 ones into a ten rod before adding tens. Partners check totals match written sums. Record steps on mini-whiteboards.

What do we do when the ones add up to more than 9?

Facilitation Tip

For Number Line Leap, draw a large number line on the floor and have students hop the tens and ones separately to reinforce place value.

What to look for

Present students with addition problems like 37 + 25. Ask them to solve it using base-10 blocks or drawings, then write the steps they took to regroup the ones. Observe their use of vocabulary like 'regroup' and 'carry over'.

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

Activity 02

• Experiential Learning
• 30 min · Pairs

Game Rotation: Dice Addition Dash

Pairs roll two dice for tens and ones to form addends, e.g., 4 and 6 make 46. Add with regrouping using drawings or blocks if needed. First pair to 10 correct sums wins a point. Rotate roles every round.

How do we record the regrouped ten in our written working?

What to look for

Give each student a card with the problem 56 + 18. Ask them to solve it and then answer: 'Where did the regrouped ten go, and why?' Collect these to check understanding of place value and the regrouping process.

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

Activity 03

• Experiential Learning
• 45 min · Small Groups

Station Circuit: Regrouping Scenarios

Set up stations with word problems, e.g., 25 apples + 38 apples. Students use straws or linking cubes to model, regroup, and solve. Include recording sheets for vertical format practice. Groups rotate after 7 minutes.

Why is regrouping not changing the total amount?

What to look for

Pose the question: 'Imagine you have 15 ones and need to add them to your tens. What do you do, and why does it help you find the total more easily?' Facilitate a class discussion where students explain the concept of regrouping.

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

Activity 04

• Experiential Learning
• 25 min · Whole Class

Whole Class: Number Line Leap

Mark a floor number line to 100. Call addends like 29 + 36. Students jump ones first, regroup at 10 by hopping to tens, then add remaining. Discuss recording as a class.

What do we do when the ones add up to more than 9?

What to look for

Present students with addition problems like 37 + 25. Ask them to solve it using base-10 blocks or drawings, then write the steps they took to regroup the ones. Observe their use of vocabulary like 'regroup' and 'carry over'.

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

A few notes on teaching this unit

Start with base-ten blocks to make regrouping tangible: 28 + 16 becomes 2 tens and 8 ones plus 1 ten and 6 ones, then trade 10 ones for 1 ten. Avoid rushing to the algorithm; instead, let students record each step vertically after the concrete experience. Research shows that students who manipulate materials before writing symbols retain place value understanding longer.

By the end of the week, students will add two-digit numbers with regrouping accurately and explain each step using place value language. They will demonstrate how a group of 10 ones becomes one ten and why the total never changes.

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Watch Out for These Misconceptions

• During Manipulative Sort, watch for students who believe exchanging 10 ones for a ten reduces the total amount of objects.

  Have students count the blocks before and after the exchange, then write the total on paper to prove the amount remains the same.

• During Dice Addition Dash, watch for students who write all ones without carrying over, e.g., 28 + 37 = 551.

  Ask students to model each roll with blocks, then write the sum vertically, placing the carried ten above the tens column before adding.

• During Regrouping Scenarios, watch for students who ignore tens when regrouping ones.

  Provide guided templates that force them to write a small 1 above the tens column, then discuss why that 1 belongs in the tens place.

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Methods used in this brief

• Experiential Learning