Building Math Skills

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Curriculum Connection

Grade Level: 3rd Grade
Subject: Mathematics
Topic: Place Value and Number Operations
Standards:

• CCSS.MATH.CONTENT.3.NBT.A.1: Use place value understanding to round whole numbers to the nearest 10 or 100.
• CCSS.MATH.CONTENT.3.NBT.A.2: Fluently add and subtract within 1000 using strategies and algorithms based on place value, properties of operations, and/or the relationship between addition and subtraction.

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Objective

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

1. Add and subtract three-digit numbers with confidence.
2. Calculate "10 more" and "100 more," as well as "10 less" and "100 less" for any given number.
3. Strengthen their understanding of place value and solidify mental math strategies.

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Materials

• Whiteboard and markers
• Individual whiteboards, markers, and erasers for students
• Handouts with practice problems
• Visual aids (place value chart)
• Colored index cards labeled with random three-digit numbers (for group activity)
• A set of "challenge cards" with situational math problems

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Lesson Structure (20 Minutes)

1. Warm-Up: Math Mini-Challenge (3 minutes)

Goal: Activate prior knowledge with a quick number sense exercise.

1. Write a three-digit number on the board (e.g., 247).
2. Rapid-fire questions:
   • “What is 10 more than 247?”
   • “What is 100 more?”
   • “What is 10 less?”
   • “What is 100 less?”
3. Allow students to shout answers, encouraging quick thinking. Identify and briefly explain any errors.

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2. Place Value Refresher (3 minutes)

Goal: Reinforce place value understanding.

1. Use a visual place value chart (Hundreds, Tens, Ones) to break apart a sample number (e.g., 562 = 500 + 60 + 2).
2. Discuss how the hundreds place changes with “100 more/less” and how the tens place changes with “10 more/less.”
3. Present a few quick “What changes?” questions to check understanding:
   • Example: "If we add 100 to 382, which digit will change?"

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3. Three-Digit Addition and Subtraction: Hands-On Practice (8 minutes)

Step 1: Mini-Lesson with Example (2 minutes)

• Write a sample problem on the whiteboard (e.g., 342 + 156).

• Work through the problem with students by:

  1. Adding the ones place: 2 + 6 = 8.
  2. Adding the tens place: 40 + 50 = 90.
  3. Adding the hundreds place: 300 + 100 = 400.
  4. Combining for the total: 498.

• Repeat with subtraction (e.g., 512 - 267), walking through the same step-by-step strategy, including borrowing if needed.

Step 2: Partner Work (6 minutes)

1. Pass out individual whiteboards to students.
2. Pair students and challenge them to solve two problems together:
   • Example: 728 + 134 and 653 - 289.
3. As students work, walk around and provide one-on-one guidance where needed.

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4. Group Activity: Math Relay (4 minutes)

Setup:

• Divide the class into three teams of three students.
• Each team takes a turn solving problems from a set of pre-prepared “challenge cards.” Examples:
  • “What is 10 more than 436?”
  • “What is 100 less than 783?”
  • “Add 312 and 259.”

Procedure:

1. A student draws a card, solves, and passes it to the next teammate for the next problem.
2. Teams earn points for correctly solving the problems within a 10-second time limit.
3. Celebrate the winning team with a fun cheer!

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5. Wrap-Up and Exit Ticket (2 minutes)

1. Recap key skills:
   • Adding and subtracting three-digit numbers.
   • Finding 10 more, 100 more, 10 less, and 100 less.
2. Quick exit question for each student to solve on their small whiteboard:
   • Example: "What is 100 less than 645?"
   • Example: "Solve 384 + 217."
3. Collect whiteboards for review and provide quick verbal praise for effort.

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Differentiation

Support for Struggling Students:

• Pair these students with a more confident partner during practice.
• Provide visual aids, such as base-ten blocks or an expanded-form breakdown for problems.

Challenge for Advanced Learners:

• Introduce challenge cards with word problems requiring multi-step addition or subtraction.
• Encourage them to explain their problem-solving process to the class.

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Assessment

• Observe student performance during partner work and group activities.
• Use correctness of exit-ticket answers as a snapshot of understanding.
• Note any students who may need a follow-up session for additional practice.

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Extension Idea

In the next math session, challenge students to create their own “math riddle” cards involving three-digit numbers, to be solved by their peers.