Rounding Rockets: Blast Off to the Nearest 100!

Mathematics Grades 4th Grade 6:59 Video
Print Lesson Plan Watch Video

Lesson Description

Learn how to round numbers to the nearest 100 using number lines and place value strategies. Get ready for a fun adventure in rounding!

Video Resource

Rounding to the nearest 100

Khan Academy

Duration: 6:59
Watch on YouTube

Key Concepts

  • Place Value (Hundreds, Tens, Ones)
  • Number Lines as a Visual Aid
  • Rounding Rules (Looking at the Tens Place)

Learning Objectives

  • Students will be able to identify the hundreds place in a given number.
  • Students will be able to round a given number to the nearest 100 using a number line.
  • Students will be able to round a given number to the nearest 100 by examining the digit in the tens place.

Educator Instructions

  • Introduction (5 mins)
    Begin by reviewing what rounding is and why we use it. Ask students for real-world examples where rounding might be helpful (e.g., estimating the cost of groceries, approximating distances).
  • Video Viewing (7 mins)
    Play the Khan Academy video 'Rounding to the nearest 100'. Encourage students to follow along and take notes on the two methods presented: using a number line and looking at the tens place.
  • Guided Practice - Number Line (8 mins)
    Work through 2-3 examples of rounding to the nearest 100 using a number line. Emphasize identifying the two nearest hundreds and plotting the number on the number line to visually determine which hundred it's closer to. Start with numbers like 238, 451, 719.
  • Guided Practice - Tens Place Rule (8 mins)
    Work through 2-3 examples of rounding to the nearest 100 by examining the digit in the tens place. Remind students of the rule: If the tens digit is 0-4, round down. If the tens digit is 5-9, round up. Use numbers like 162, 385, 647.
  • Independent Practice (10 mins)
    Provide students with a worksheet containing a variety of numbers to round to the nearest 100. Encourage them to use either the number line method or the tens place rule, and to check their answers using the opposite method.
  • Wrap-up and Review (2 mins)
    Briefly review the key concepts and strategies for rounding to the nearest 100. Answer any remaining questions.

Interactive Exercises

  • Number Line Rounding Game
    Draw a large number line on the board. Call out numbers and have students come up and place them on the number line. Then, ask them to round the number to the nearest 100 and explain their reasoning.
  • Rounding Relay Race
    Divide the class into teams. Write a list of numbers on the board. One student from each team races to the board, rounds the first number to the nearest 100, and then tags the next teammate. The first team to correctly round all the numbers wins.

Discussion Questions

  • Why is it helpful to be able to round numbers?
  • Can you think of a time when rounding to the nearest 100 would be useful in everyday life?
  • What are the two strategies we learned for rounding to the nearest 100? Which one do you prefer and why?

Skills Developed

  • Place Value Understanding
  • Estimation Skills
  • Problem-Solving

Multiple Choice Questions

Question 1:

What is 345 rounded to the nearest 100?

Correct Answer: 300

Question 2:

To round to the nearest 100, which place value do you look at?

Correct Answer: Tens place

Question 3:

What is 762 rounded to the nearest 100?

Correct Answer: 850

Question 4:

What is 982 rounded to the nearest 100?

Correct Answer: 1000

Question 5:

If the tens digit is 4, do you round up or down when rounding to the nearest 100?

Correct Answer: Round down

Question 6:

What is 519 rounded to the nearest 100?

Correct Answer: 500

Question 7:

What number is exactly in the middle of 600 and 700?

Correct Answer: 650

Question 8:

Which of these numbers rounds to 200 when rounding to the nearest 100?

Correct Answer: 149

Question 9:

Is 850 closer to 800 or 900?

Correct Answer: 900

Question 10:

What is 123 rounded to the nearest 100?

Correct Answer: 100

Fill in the Blank Questions

Question 1:

To round to the nearest 100, look at the ______ place.

Correct Answer: tens

Question 2:

If the tens digit is 6, you round ____.

Correct Answer: up

Question 3:

450 is exactly halfway between 400 and ______.

Correct Answer: 500

Question 4:

712 rounded to the nearest 100 is ______.

Correct Answer: 700

Question 5:

Rounding helps us to ________ numbers.

Correct Answer: estimate

Question 6:

987 rounded to the nearest 100 is _______.

Correct Answer: 1000

Question 7:

A _________ can help us see which 100 a number is closest to.

Correct Answer: number line

Question 8:

349 is closer to 300 than to ________.

Correct Answer: 400

Question 9:

When rounding to the nearest 100, if the tens place is 5 or more, you round ____.

Correct Answer: up

Question 10:

222 rounded to the nearest 100 is _________.

Correct Answer: 200

Educational Standards

4.N.1.1:Read, write, discuss, and represent whole numbers up to 1,000,000. Representations may include numerals, words, pictures, number lines, and manipulatives. 4.N.1.2:Use place value to describe whole numbers between 1,000 and 1,000,000 in terms of millions, hundred thousands, ten thousands, thousands, hundreds, tens, and ones with written, standard, and expanded forms. 4.N.2.3:Estimate products of 3-digit by 1-digit and 2-digit by 2-digit whole number factors using a variety of strategies (e.g., rounding, front end estimation, adjusting, compatible numbers) to assess the reasonableness of results. Explore larger numbers using technology to investigate patterns.

Teaching Materials

Download ready-to-use materials for this lesson:

Student Worksheet Classroom Slides Assessment Quiz
Add to Google Classroom

User Actions

Sign in to save this lesson plan to your favorites.

Sign In

Share This Lesson

Related Lesson Plans