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10 More, 10 Less, Can You Guess?

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Lesson Plan

10 More, 10 Less, Can You Guess?

Students will be able to apply mental math strategies to find 10 more or 10 less than a given two-digit number, and determine if addition/subtraction equations are true using the equal sign.

Mastering mental math strategies for 10 more/less builds a strong foundation for place value understanding and quick calculation skills, making math less daunting and more accessible. Understanding the equal sign ensures students grasp the balance of equations, a fundamental concept for all future math.

Audience

1st Grade Students

Time

3 Days, 50 minutes per day

Approach

Whole-class instruction, guided practice, and independent application.

Materials

Whiteboard or Projector, Markers or Pens, Spiral Review OA.7 Worksheets, 10 More Script, 10 More Slide Deck, 10 More Worksheet, 10 More Answer Key, 10 Less Script, 10 Less Slide Deck, 10 Less Worksheet, 10 Less Answer Key, 10 More or Less Script, 10 More or Less Slide Deck, 10 More or Less Worksheet, and 10 More or Less Answer Key

Prep

Teacher Preparation

30 minutes (per day)

  • Review all lesson plans, scripts, slide decks, and worksheets for the day.
    - Print copies of Spiral Review OA.7 Worksheets, 10 More Worksheet, 10 Less Worksheet, and 10 More or Less Worksheet for each student.
    - Ensure projector/whiteboard is ready.
    - Gather markers/pens.
    - Prepare for small group instruction by reviewing student data and grouping students as needed to provide targeted support or enrichment activities.
    - Review the generated materials as needed.

Step 1

Day 1: Spiral Review & 10 More

50 Minutes

Whole Group (5 minutes): Spiral Review OA.7

  • Distribute Spiral Review OA.7 Worksheets (Day 1).
  • Guide students through 1-2 problems together.
  • Students complete the remaining problems independently.

Whole Group (15 minutes): Lesson: '10 More'

  • Follow the 10 More Script using the 10 More Slide Deck.
  • I Do: Model finding 10 more than a number using a hundreds chart and mental math.
  • We Do: Practice finding 10 more with student participation.
  • You Do: Students attempt a few problems independently on their mini-whiteboards or scrap paper.

Small Group (30 minutes): Differentiated Practice

  • Group 1 (Intervention): Work with students needing extra support on '10 More'. Use manipulatives (like base ten blocks) to build numbers and add 10. Focus on understanding the tens place change.
  • Group 2 (On-Level): Students work on the 10 More Worksheet. Circulate to provide support.
  • Group 3 (Enrichment): Challenge students with finding 10 more than a three-digit number or create their own '10 More' problems.

Wrap-Up (As time allows):

  • Quick check for understanding from the worksheet or exit ticket question (e.g., "What is 10 more than 35?").

Step 2

Day 2: Spiral Review & 10 Less

50 Minutes

Whole Group (5 minutes): Spiral Review OA.7

  • Distribute Spiral Review OA.7 Worksheets (Day 2).
  • Guide students through 1-2 problems together.
  • Students complete the remaining problems independently.

Whole Group (15 minutes): Lesson: '10 Less'

  • Follow the 10 Less Script using the 10 Less Slide Deck.
  • I Do: Model finding 10 less than a number using a hundreds chart and mental math.
  • We Do: Practice finding 10 less with student participation.
  • You Do: Students attempt a few problems independently on their mini-whiteboards or scrap paper.

Small Group (30 minutes): Differentiated Practice

  • Group 1 (Intervention): Work with students needing extra support on '10 Less'. Use manipulatives (like base ten blocks) to build numbers and subtract 10. Focus on understanding the tens place change.
  • Group 2 (On-Level): Students work on the 10 Less Worksheet. Circulate to provide support.
  • Group 3 (Enrichment): Challenge students with finding 10 less than a three-digit number or create their own '10 Less' problems.

Wrap-Up (As time allows):

  • Quick check for understanding from the worksheet or exit ticket question (e.g., "What is 10 less than 62?").

Step 3

Day 3: Spiral Review & 10 More or Less

50 Minutes

Whole Group (5 minutes): Spiral Review OA.7

  • Distribute Spiral Review OA.7 Worksheets (Day 3).
  • Guide students through 1-2 problems together.
  • Students complete the remaining problems independently.

Whole Group (15 minutes): Lesson: '10 More or Less'

  • Follow the 10 More or Less Script using the 10 More or Less Slide Deck.
  • I Do: Model finding both 10 more AND 10 less than a number. Discuss how the tens place changes.
  • We Do: Practice finding 10 more or 10 less with student participation, identifying whether to add or subtract 10.
  • You Do: Students attempt a few problems independently on their mini-whiteboards or scrap paper.

Small Group (30 minutes): Differentiated Practice

  • Group 1 (Intervention): Focus on consolidating both '10 More' and '10 Less'. Use a hundreds chart and manipulatives. Provide number sentences where students have to identify if it's 10 more or 10 less.
  • Group 2 (On-Level): Students work on the 10 More or Less Worksheet.
  • Group 3 (Enrichment): Students play a '10 More, 10 Less' game with a partner using dice or number cards, challenging each other. Or, give them multi-step problems (e.g., "Start at 45, find 10 more, then find 10 less").

Wrap-Up (As time allows):

  • Quick check for understanding: "Tell me a number, and I'll tell you 10 more and 10 less!"
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Worksheet

Spiral Review: True or False Equations? (Day 1)

Directions: Look at each equation. Is it true or false? Circle your answer.

  1. 5 + 3 = 8
    True / False



  2. 7 - 2 = 4
    True / False



  3. 6 = 1 + 5
    True / False



  4. 10 - 3 = 6
    True / False



  5. 4 + 4 = 8
    True / False



  6. 9 - 1 = 7
    True / False



Spiral Review: True or False Equations? (Day 2)

Directions: Look at each equation. Is it true or false? Circle your answer.

  1. 2 + 7 = 9
    True / False



  2. 8 - 5 = 2
    True / False



  3. 12 = 6 + 6
    True / False



  4. 11 - 4 = 8
    True / False



  5. 3 + 9 = 12
    True / False



  6. 10 - 7 = 3
    True / False



Spiral Review: True or False Equations? (Day 3)

Directions: Look at each equation. Is it true or false? Circle your answer.

  1. 6 + 4 = 10
    True / False



  2. 9 - 2 = 6
    True / False



  3. 15 = 7 + 8
    True / False



  4. 13 - 5 = 7
    True / False



  5. 5 + 5 = 10
    True / False



  6. 14 - 6 = 9
    True / False



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lenny

Slide Deck

Ready for 10 More?

Today, we're going on a treasure hunt for numbers!

We'll learn a super speedy way to find 10 MORE than any number!

Welcome students and introduce the topic of finding 10 more. Connect it to real-life situations like counting in tens.

The Magic of 10 More!

When we say '10 more,' it means we're adding 10!

Look at a hundreds chart:

  • Start at 15.
  • Go down one row.
  • You land on... 25! So, 10 more than 15 is 25!

Introduce the concept of '10 more' using a hundreds chart. Highlight how adding 10 moves you directly down one row. Show an example like 15 + 10 = 25.

Mental Math Trick!

Here's the secret:

  • When you add 10, the ones digit stays the SAME.
  • The tens digit goes UP by 1.

Let's try it!

  • What is 10 more than 23?
    • The 3 (ones) stays.
    • The 2 (tens) goes up to 3.
    • So, 10 more than 23 is... 33!

Explain the mental math strategy: only the tens digit changes, the ones digit stays the same. Use an example like 23 -> 33. Emphasize the 'ones stay, tens go up one!' rule.

Let's Practice Together!

What is 10 more than these numbers?

  • 10 more than 47 is...?
  • 10 more than 51 is...?
  • 10 more than 70 is...?

Remember: Ones stay, tens go up one!

Guided practice ('We Do'). Ask students to find 10 more for several numbers. Encourage them to explain their thinking using the tens and ones rule. Use a hundreds chart if needed.

Your Turn!

Find 10 more for these numbers on your own:

  • 10 more than 34 = ?
  • 10 more than 68 = ?
  • 10 more than 82 = ?

Show me your answers!

Independent practice ('You Do'). Students can write answers on mini-whiteboards. Observe their understanding and provide immediate feedback.

Great Job, Detectives!

You are now 10-more experts!

Keep practicing this mental math trick!

Next time, we'll explore 10 LESS!

Conclude the lesson by reviewing the key takeaway and previewing the next concept.

lenny

Script

10 More Script

Slide 1: Ready for 10 More?

Teacher: Good morning, mathematicians! Today, we're going on a super fun treasure hunt for numbers! Our mission is to become experts at finding 10 MORE than any number. Does that sound exciting? It's a secret superpower for your brain!

Slide 2: The Magic of 10 More!

Teacher: When we say '10 more,' what do you think that means we're doing with numbers? (Pause for responses). That's right! It means we're adding 10! Now, let's look at our hundreds chart on the board. (Point to the hundreds chart). If I start at the number 15, and I want to find 10 more, I can just go straight down one row. Watch what happens! I start at 15, and when I go down, I land on... (point) 25! So, 10 more than 15 is 25! Did you see how easy that was? It's like magic!

Teacher: Let's try another one. If I start at 32 and I want to find 10 more, where do you think I'll land? (Point to 32, trace down). Yes! 42! So, 10 more than 32 is 42. Amazing!

Slide 3: Mental Math Trick!

Teacher: Now, here's an even faster trick – a mental math secret! You won't even need a hundreds chart for this one, once you get good at it! When you add 10 to a number, something special happens to the digits. Let's look at our example: 15 became 25. The '5' in the ones place stayed the same, right? But the '1' in the tens place changed to a '2'. It went UP by 1!

Teacher: So, here's the secret rule: When you add 10, the ones digit stays the SAME, and the tens digit goes UP by 1. Let's try it with a new number. What is 10 more than 23? Think about our rule. The 3 (in the ones place) stays the same. The 2 (in the tens place) goes up by 1, so it becomes a 3. So, 10 more than 23 is... (pause) 33! You got it!

Teacher: Let's try another one: 10 more than 41. What stays the same? The 1 in the ones place. What changes? The 4 in the tens place goes up by 1 to a 5. So 10 more than 41 is... 51! You're getting so good at this!

Slide 4: Let's Practice Together!

Teacher: Alright, my number detectives, it's time for our 'We Do' part! Let's practice finding 10 more together. Remember our secret rule: 'Ones stay, tens go up one!'

  • What is 10 more than 47? Think about the ones and tens. (Pause for student responses). The 7 stays the same, and the 4 goes up to 5. So, 10 more than 47 is 57! Fantastic!
  • What is 10 more than 51? (Pause for responses). Yes, 61! The 1 stays, the 5 goes to 6.
  • What is 10 more than 70? This one is tricky because of the zero in the ones place. Does the zero change? No! So, the 0 stays. What about the 7 in the tens place? It goes up to 8. So, 10 more than 70 is... 80! Excellent thinking!

Slide 5: Your Turn!

Teacher: Now it's your turn for the 'You Do' part! I want you to try these on your own. You can use your mini-whiteboards or a piece of scrap paper. Show me your answers when you have them!

  • What is 10 more than 34? Write it down!
  • What is 10 more than 68? Show me!
  • What is 10 more than 82? Let's see your super speedy brains in action!

(Circulate, check answers, provide individual support and praise.)

Slide 6: Great Job, Detectives!

Teacher: Wow! You are all 10-more experts! Give yourselves a pat on the back. You've learned a fantastic mental math trick today. Keep practicing this, and you'll be able to find 10 more than any number super quickly in your head!

Teacher: Tomorrow, we're going to explore the opposite... we'll learn about finding 10 LESS! Get ready for another number adventure!

lenny
lenny

Worksheet

10 More Mania!

Directions: Find 10 more than each number. Use your mental math trick or a hundreds chart if you need help!

  1. 10 more than 12 =


  2. 10 more than 29 =


  3. 10 more than 30 =


  4. 10 more than 45 =


  5. 10 more than 53 =


  6. 10 more than 67 =


  7. 10 more than 71 =


  8. 10 more than 88 =


  9. 10 more than 9 =


  10. 10 more than 90 =


Challenge!

What is 10 more than 99?





Draw a picture to show 10 more than 24.












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lenny

Answer Key

10 More Mania! Answer Key

Directions: Find 10 more than each number. Use your mental math trick or a hundreds chart if you need help!

  1. 10 more than 12 = 22
    Thought Process: The ones digit (2) stays the same. The tens digit (1) increases by 1 to 2.


  2. 10 more than 29 = 39
    Thought Process: The ones digit (9) stays the same. The tens digit (2) increases by 1 to 3.


  3. 10 more than 30 = 40
    Thought Process: The ones digit (0) stays the same. The tens digit (3) increases by 1 to 4.


  4. 10 more than 45 = 55
    Thought Process: The ones digit (5) stays the same. The tens digit (4) increases by 1 to 5.


  5. 10 more than 53 = 63
    Thought Process: The ones digit (3) stays the same. The tens digit (5) increases by 1 to 6.


  6. 10 more than 67 = 77
    Thought Process: The ones digit (7) stays the same. The tens digit (6) increases by 1 to 7.


  7. 10 more than 71 = 81
    Thought Process: The ones digit (1) stays the same. The tens digit (7) increases by 1 to 8.


  8. 10 more than 88 = 98
    Thought Process: The ones digit (8) stays the same. The tens digit (8) increases by 1 to 9.


  9. 10 more than 9 = 19
    Thought Process: For single-digit numbers, think of it as 09. The ones digit (9) stays the same. The tens digit (0) increases by 1 to 1.


  10. 10 more than 90 = 100
    Thought Process: The ones digit (0) stays the same. The tens digit (9) increases by 1, which means it rolls over to 10 in the tens place, making it 100.


Challenge!

What is 10 more than 99? 109
Thought Process: The ones digit (9) stays the same. The tens digit (9) increases by 1, which means it rolls over to 10 in the tens place, making it 109.



Draw a picture to show 10 more than 24.
Visual representation showing 2 tens and 4 ones, then adding another group of 10. The final picture should show 3 tens and 4 ones.

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lenny

Slide Deck

Let's Find 10 Less!

Today, we're going to practice another super-fast number trick!

We'll learn how to find 10 LESS than any number with mental math!

Welcome students and introduce the topic of finding 10 less. Connect it to taking away 10.

The Power of 10 Less!

When we say '10 less,' it means we're subtracting 10!

Look at a hundreds chart:

  • Start at 35.
  • Go up one row.
  • You land on... 25! So, 10 less than 35 is 25!

Introduce the concept of '10 less' using a hundreds chart. Highlight how subtracting 10 moves you directly up one row. Show an example like 35 - 10 = 25.

Mental Math Trick (Again)!

Here's the secret for 10 less:

  • When you subtract 10, the ones digit stays the SAME.
  • The tens digit goes DOWN by 1.

Let's try it!

  • What is 10 less than 48?
    • The 8 (ones) stays.
    • The 4 (tens) goes down to 3.
    • So, 10 less than 48 is... 38!

Explain the mental math strategy: only the tens digit changes, the ones digit stays the same. Use an example like 48 -> 38. Emphasize the 'ones stay, tens go down one!' rule.

Practice Makes Perfect!

What is 10 less than these numbers?

  • 10 less than 63 is...?
  • 10 less than 20 is...?
  • 10 less than 75 is...?

Remember: Ones stay, tens go down one!

Guided practice ('We Do'). Ask students to find 10 less for several numbers. Encourage them to explain their thinking using the tens and ones rule. Use a hundreds chart if needed.

Your Turn to Shine!

Find 10 less for these numbers on your own:

  • 10 less than 56 = ?
  • 10 less than 91 = ?
  • 10 less than 30 = ?

Show me your answers!

Independent practice ('You Do'). Students can write answers on mini-whiteboards. Observe their understanding and provide immediate feedback.

Awesome Job, Subtractors!

You are now 10-less masters!

Keep practicing this mental math trick!

Next time, we'll decide if it's 10 MORE or 10 LESS!

Conclude the lesson by reviewing the key takeaway and previewing the next concept.

lenny

Script

10 Less Script

Slide 1: Let's Find 10 Less!

Teacher: Hello, amazing mathematicians! Yesterday, we were number detectives finding 10 MORE. Today, we have a new mission! We're going to learn how to find 10 LESS than any number, super fast, using our mental math brains! Are you ready for another number adventure?

Slide 2: The Power of 10 Less!

Teacher: When we say '10 less,' what do you think that means we're doing with numbers? (Pause for responses). That's right! It means we're subtracting 10! Just like adding 10 had a pattern on the hundreds chart, so does subtracting 10.

Teacher: Let's look at our hundreds chart again. (Point to the hundreds chart). If I start at the number 35, and I want to find 10 less, I move UP one row. Watch what happens! I start at 35, and when I go up, I land on... (point) 25! So, 10 less than 35 is 25! See the pattern?

Teacher: Let's try another one. If I start at 62 and I want to find 10 less, where do you think I'll land? (Point to 62, trace up). Yes! 52! So, 10 less than 62 is 52. You're catching on quickly!

Slide 3: Mental Math Trick (Again)!

Teacher: Just like with 10 more, there's a secret mental math trick for 10 less too! It's very similar, but we're going the other way. When you subtract 10 from a number, what do you notice about the digits? Let's look at our example: 35 became 25. The '5' in the ones place stayed the same, didn't it? But the '3' in the tens place changed to a '2'. It went DOWN by 1!

Teacher: So, here's our secret rule for 10 less: The ones digit stays the SAME, and the tens digit goes DOWN by 1. Let's try it with a new number. What is 10 less than 48? Think about our rule. The 8 (in the ones place) stays the same. The 4 (in the tens place) goes down by 1, so it becomes a 3. So, 10 less than 48 is... (pause) 38! Amazing!

Teacher: Let's try another one: 10 less than 71. What stays the same? The 1 in the ones place. What changes? The 7 in the tens place goes down by 1 to a 6. So 10 less than 71 is... 61! You've got this!

Slide 4: Practice Makes Perfect!

Teacher: Alright, my number ninjas, it's our 'We Do' part! Let's practice finding 10 less together. Remember our secret rule: 'Ones stay, tens go down one!'

  • What is 10 less than 63? Think about the ones and tens. (Pause for student responses). The 3 stays the same, and the 6 goes down to 5. So, 10 less than 63 is 53! Excellent!
  • What is 10 less than 20? (Pause for responses). Yes, 10! The 0 stays, the 2 goes to 1. Good job!
  • What is 10 less than 75? (Pause for responses). You're right, 65! The 5 stays, the 7 goes down to 6.

Slide 5: Your Turn to Shine!

Teacher: Now it's your turn for the 'You Do' part! I want you to try these on your own. You can use your mini-whiteboards or a piece of scrap paper. Show me your answers when you have them!

  • What is 10 less than 56? Write it down!
  • What is 10 less than 91? Show me!
  • What is 10 less than 30? Let's see your super speedy brains in action!

(Circulate, check answers, provide individual support and praise.)

Slide 6: Awesome Job, Subtractors!

Teacher: Fantastic work, everyone! You are now 10-less masters. Give yourselves a round of applause! You've learned another super important mental math trick today. Keep practicing this, and you'll be able to find 10 less than any number quickly!

Teacher: Next time, we'll put both our skills together and decide if we need to find 10 MORE or 10 LESS! Get ready for a number challenge!"

lenny
lenny

Worksheet

10 Less Challenge!

Directions: Find 10 less than each number. Use your mental math trick or a hundreds chart if you need help!

  1. 10 less than 23 =


  2. 10 less than 37 =


  3. 10 less than 50 =


  4. 10 less than 64 =


  5. 10 less than 79 =


  6. 10 less than 81 =


  7. 10 less than 48 =


  8. 10 less than 95 =


  9. 10 less than 16 =


  10. 10 less than 100 =


Challenge!

What is 10 less than 11?





Draw a picture to show 10 less than 42.












lenny
lenny

Answer Key

10 Less Challenge! Answer Key

Directions: Find 10 less than each number. Use your mental math trick or a hundreds chart if you need help!

  1. 10 less than 23 = 13
    Thought Process: The ones digit (3) stays the same. The tens digit (2) decreases by 1 to 1.


  2. 10 less than 37 = 27
    Thought Process: The ones digit (7) stays the same. The tens digit (3) decreases by 1 to 2.


  3. 10 less than 50 = 40
    Thought Process: The ones digit (0) stays the same. The tens digit (5) decreases by 1 to 4.


  4. 10 less than 64 = 54
    Thought Process: The ones digit (4) stays the same. The tens digit (6) decreases by 1 to 5.


  5. 10 less than 79 = 69
    Thought Process: The ones digit (9) stays the same. The tens digit (7) decreases by 1 to 6.


  6. 10 less than 81 = 71
    Thought Process: The ones digit (1) stays the same. The tens digit (8) decreases by 1 to 7.


  7. 10 less than 48 = 38
    Thought Process: The ones digit (8) stays the same. The tens digit (4) decreases by 1 to 3.


  8. 10 less than 95 = 85
    Thought Process: The ones digit (5) stays the same. The tens digit (9) decreases by 1 to 8.


  9. 10 less than 16 = 6
    Thought Process: The ones digit (6) stays the same. The tens digit (1) decreases by 1 to 0. So it becomes 6.


  10. 10 less than 100 = 90
    Thought Process: The ones digit (0) stays the same. The tens digit (0) in 100 becomes 9 (from 10 tens down to 9 tens).


Challenge!

What is 10 less than 11? 1
Thought Process: The ones digit (1) stays the same. The tens digit (1) decreases by 1 to 0.


Draw a picture to show 10 less than 42.
Visual representation showing 4 tens and 2 ones, then crossing out one group of 10. The final picture should show 3 tens and 2 ones.

lenny
lenny

Slide Deck

10 More OR 10 Less?

We've learned two super cool number tricks:

  • Finding 10 MORE
  • Finding 10 LESS

Today, we're going to decide which trick to use!

Welcome students and remind them of what they've learned about 10 more and 10 less. Introduce the idea of choosing the correct operation.

Quick Review: 10 More!

Remember our 10 MORE trick?

  • The ones digit stays the SAME.
  • The tens digit goes UP by 1.

What is 10 more than 52?

(52 -> 62)

Review 10 More: quickly recap the rule (ones stay, tens go up one) and do a quick example.

Quick Review: 10 Less!

Remember our 10 LESS trick?

  • The ones digit stays the SAME.
  • The tens digit goes DOWN by 1.

What is 10 less than 78?

(78 -> 68)

Review 10 Less: quickly recap the rule (ones stay, tens go down one) and do a quick example.

The Big Decision!

Sometimes, you'll need to decide!

Let's try a number: 43

  • What is 10 more than 43?
  • What is 10 less than 43?

(Discuss how the tens digit changes up or down.)

Introduce mixed practice. Present a number and ask students to find both 10 more and 10 less. Emphasize carefully reading the question.

Together, We Decide!

Let's practice together!

  1. Start at 36. Find 10 MORE.
  2. Start at 81. Find 10 LESS.
  3. Start at 29. Find 10 MORE.
  4. Start at 50. Find 10 LESS.

Guided practice ("We Do"). Present a number and a phrase (10 more or 10 less). Ask students to solve and explain. Repeat for a few examples.

Your Mission: Choose Wisely!

It's your turn!

Find the answer for each:

  • 10 more than 17 = ?
  • 10 less than 44 = ?
  • 10 more than 73 = ?
  • 10 less than 90 = ?
  • 10 more than 6 = ?

Independent practice ("You Do"). Students work on mini-whiteboards. Present a series of mixed problems. Circulate and provide support.

You're Mental Math Wizards!

Amazing work today!

You can now find 10 more AND 10 less!

Keep using your mental math tricks!

Conclude the lesson by praising their effort and reinforcing the importance of mental math for place value.

lenny

Script

10 More or Less Script

Slide 1: 10 More OR 10 Less?

Teacher: Good morning, super math thinkers! You have become experts at two very important number tricks: finding 10 MORE than a number and finding 10 LESS than a number. Today, our challenge is to decide which trick to use! Are you ready to be number decision-makers?

Slide 2: Quick Review: 10 More!

Teacher: Let's quickly remember our 10 MORE trick. What happens to the ones digit when we find 10 more? (Pause). It stays the same! And what happens to the tens digit? (Pause). It goes UP by 1! So, what is 10 more than 52? (Pause for response). Yes, 62! The 2 stays, the 5 goes to a 6.

Slide 3: Quick Review: 10 Less!

Teacher: Now, let's quickly remember our 10 LESS trick. What happens to the ones digit when we find 10 less? (Pause). It stays the same! And what happens to the tens digit? (Pause). It goes DOWN by 1! So, what is 10 less than 78? (Pause for response). That's right, 68! The 8 stays, the 7 goes to a 6.

Slide 4: The Big Decision!

Teacher: Okay, here's where it gets exciting! Sometimes, you'll need to decide if you're looking for 10 MORE or 10 LESS. Let's take the number 43. If I ask you, "What is 10 more than 43?" what would you say? (Pause). Right, 53! The tens digit went up.

Teacher: Now, if I ask, "What is 10 less than 43?" what would you say? (Pause). You got it, 33! The tens digit went down. See how important it is to listen carefully to whether I say "more" or "less"?

Slide 5: Together, We Decide!

Teacher: It's time for our 'We Do' part! Let's work together to make the right choice – 10 more or 10 less? Read carefully!

  1. Start at 36. Find 10 MORE. What's the answer? (Pause). Yes, 46! We increased the tens digit.
  2. Start at 81. Find 10 LESS. What's the answer? (Pause). Good job, 71! We decreased the tens digit.
  3. Start at 29. Find 10 MORE. What's the answer? (Pause). You're on fire, 39! Tens digit went up.
  4. Start at 50. Find 10 LESS. What's the answer? (Pause). Perfect, 40! Tens digit went down.

You are becoming incredible number choosers!

Slide 6: Your Mission: Choose Wisely!

Teacher: Now, it's your turn for the 'You Do' part! On your mini-whiteboards or scrap paper, solve these problems. Read each one carefully to decide if you need to find 10 MORE or 10 LESS. Show me your answers when you're done!

  • 10 more than 17 =


  • 10 less than 44 =


  • 10 more than 73 =


  • 10 less than 90 =


  • 10 more than 6 =


(Circulate, observe, and provide individual support as needed. Praise good choices and correct any misunderstandings.)

Slide 7: You're Mental Math Wizards!

Teacher: Give yourselves a big round of applause! You've done an amazing job today distinguishing between 10 more and 10 less. You are truly becoming mental math wizards! These skills will help you so much with bigger numbers and harder math later on. Keep practicing these fantastic mental math tricks!

Teacher: We are all done with our unit on 10 More, 10 Less, Can You Guess? Great work, everyone!

lenny
lenny

Worksheet

10 More or Less: The Ultimate Challenge!

Directions: Read each question carefully and decide if you need to find 10 MORE or 10 LESS. Then write your answer!

  1. What is 10 more than 25?


  2. What is 10 less than 87?


  3. Start at 41. Find 10 more.


  4. Start at 19. Find 10 less.


  5. What is 10 more than 60?


  6. What is 10 less than 33?


  7. Start at 76. Find 10 more.


  8. Start at 92. Find 10 less.


  9. I have 54 apples. I pick 10 more. How many apples do I have now?


  10. My friend has 28 candies. She eats 10. How many candies does she have left?


Brain Buster!

Start at 30. Find 10 more, then find 10 less. What number do you end up on?





lenny
lenny

Answer Key

10 More or Less: The Ultimate Challenge! Answer Key

Directions: Read each question carefully and decide if you need to find 10 MORE or 10 LESS. Then write your answer!

  1. What is 10 more than 25? 35
    Thought Process: The ones digit (5) stays the same. The tens digit (2) increases by 1 to 3.


  2. What is 10 less than 87? 77
    Thought Process: The ones digit (7) stays the same. The tens digit (8) decreases by 1 to 7.


  3. Start at 41. Find 10 more. 51
    Thought Process: The ones digit (1) stays the same. The tens digit (4) increases by 1 to 5.


  4. Start at 19. Find 10 less. 9
    Thought Process: The ones digit (9) stays the same. The tens digit (1) decreases by 1 to 0.


  5. What is 10 more than 60? 70
    Thought Process: The ones digit (0) stays the same. The tens digit (6) increases by 1 to 7.


  6. What is 10 less than 33? 23
    Thought Process: The ones digit (3) stays the same. The tens digit (3) decreases by 1 to 2.


  7. Start at 76. Find 10 more. 86
    Thought Process: The ones digit (6) stays the same. The tens digit (7) increases by 1 to 8.


  8. Start at 92. Find 10 less. 82
    Thought Process: The ones digit (2) stays the same. The tens digit (9) decreases by 1 to 8.


  9. I have 54 apples. I pick 10 more. How many apples do I have now? 64 apples
    Thought Process: "10 more" means adding 10. The ones digit (4) stays the same. The tens digit (5) increases by 1 to 6.


  10. My friend has 28 candies. She eats 10. How many candies does she have left? 18 candies
    Thought Process: "Eats 10" means subtracting 10. The ones digit (8) stays the same. The tens digit (2) decreases by 1 to 1.


Brain Buster!

Start at 30. Find 10 more, then find 10 less. What number do you end up on? 30
Thought Process: 10 more than 30 is 40. Then 10 less than 40 is 30. You end up back at the starting number.

lenny
lenny