Grouping with Tens

Grade Level

1st and 2nd Grade

Duration

45 minutes

Class Size

18 students

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Common Core Standards

• 1.NBT.B.2
  Understand that the two digits of a two-digit number represent amounts of tens and ones (e.g., 45 has 4 tens, 5 ones).

• 2.NBT.A.1
  Understand that the three digits of a three-digit number represent amounts of hundreds, tens, and ones; understand the following as special cases:

  • 100 can be thought of as a bundle of ten tens — called a "hundred."

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Learning Objectives

By the end of this lesson, students will be able to:

1. Group objects into tens and ones practically.
2. Demonstrate understanding of place value by identifying the number of tens and ones represented by groups of objects.
3. Use place value language ("tens" and "ones") to describe numbers up to 100.
4. Write simple two-digit numbers to represent grouped objects.

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Materials Needed

• Base-10 blocks (units and rods)
• Whiteboards and dry erase markers (1 per student)
• Chart paper with visual of tens and ones grid (1 large for class)
• 200 small counters (e.g., beans, buttons, or cubes, enough for 18 students)
• Number cards (10-99)
• Grouping mats with sections for 'Tens' and 'Ones' (1 per student)
• Timer or stopwatch
• "Tens and Ones" stickers or stamps (for positive reinforcement)

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Lesson Breakdown

1. Introduction & Warm-up (5 minutes)

• Engage: Begin by counting aloud together from 1 to 20, emphasize “ten” when you reach it.
• Ask students: “How many tens do you see in the number 14? What about the ones?” Briefly discuss.
• Show a two-digit number card (e.g., 24) and ask the class what they notice about it (focus student responses on “tens” and “ones”).
• Explain today’s goal: “We are going to learn how to group objects into tens and ones, to better understand what two-digit numbers mean.”

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2. Direct Instruction with Modeling (10 minutes)

• Use the large chart paper and base-10 blocks.
• Place 13 unit blocks on the table.
• Model grouping: Take 10 blocks and bundle them together as one “ten” rod.
• Show students the group labeled “1 ten” and leftover “3 ones.”
• Write on the chart: "13 = 1 ten + 3 ones."
• Repeat with 27 units: group into two tens and seven ones.
• Encourage students to use place value words: "two tens and seven ones."
• Show connection between grouping and writing two-digit numbers.

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3. Guided Practice - Hands-on Grouping (15 minutes)

• Distribute grouping mats, counters, and base-10 unit blocks.
• Assign each student a number card (from 10 to 99).
• Students count out counters to represent their number.
• Guide them to physically group counters into tens bundles and leftover ones on their mat.
• Circulate the room, asking:
  • “How many groups of ten do you have?”
  • “How many single ones are left?”
  • “What number does that make?”
• After grouping, students write their number on the whiteboard and hold it up.

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4. Collaborative Learning (8 minutes)

• Pair students to compare their numbers.
• Partners explain their tens and ones groups to each other.
• They create a small poster on a shared sheet:
  • Draw bundles of tens and dots for ones to represent their number.
  • Write the number using place value terms and digits.
• Optional: Use the "Tens and Ones" stickers for positive encouragement on their posters.

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5. Closing & Assessment (7 minutes)

• Review 3–4 students’ number posters with the class.
• Ask reflective questions:
  • “Why is it easier to understand numbers when we group in tens?”
  • “What is one thing you learned about tens and ones today?”
• Quick formative check:
  • Show a number card (e.g., 54).
  • Students write on whiteboards how many tens and ones they see.
• Collect whiteboards to assess individual student understanding.

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Differentiation

• For struggling learners: Provide smaller numbers (under 30) for easier grouping.
• For advanced learners: Challenge them by asking how a number changes if one ten is added or taken away.
• Offer extra visual aids or one-on-one support during guided practice.

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Reflection and Follow-up

• Homework suggestion: Ask students to bring objects from home (e.g., pencils or small toys) and group them into tens and ones, drawing a picture or writing the number.
• Next lesson preview: “We will learn how to add and subtract using our knowledge of tens and ones!”

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Teacher Tips to Wow Your Class

• Use bright and tactile materials to keep engagement high.
• Incorporate movement by having students physically group counters on desks or tables.
• Introduce simple songs or chants about tens and ones to reinforce concepts rhythmically.
• Capture student work photos for a “Tens and Ones Gallery” in the classroom showcasing their understanding.
• Praise and celebrate small successes frequently to build confidence.

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This detailed lesson carefully aligns to Common Core standards, promotes kinesthetic learning, and encourages collaboration, making place value concepts tangible and exciting for young learners.