Unit 16: Whole-Number Arithmetic Fluency

Day 4 of 30

Round to nearest 10, 100, and 1000

3-5Mathematics

Content is AI-assisted and continuously improved through educator review

Learning Objective

Students will be able to round to nearest 10, 100, and 1000.

Today's Lesson

In this lesson, we'll explore how to round to nearest 10, 100, and 1000. Mathematical thinking develops logical reasoning and problem-solving abilities.

Rounding means changing a number to a nearby number that's easier to work with. We round to the nearest 10, 100, 1000, etc. The rule: If the digit to the right is 5 or more, round up. If it's 4 or less, round down. For example, 47 rounds to 50 (because 7 ≥ 5), but 43 rounds to 40 (because 3 < 5). The rounded number keeps place value zeros. Rounding helps with estimation and mental math!

As you work through today's material, pay attention to the examples and try to identify the patterns or strategies being used. This will help you apply these concepts to new problems.

Take notes on key points and make connections to what you've already learned in previous lessons.

Key Terms
Problem

A mathematical question requiring analysis and solution

Solution

The result obtained by solving a problem

Activities
Instructions
1. Review the example problems for round to nearest 10, 100, and 1000. 2. Identify the steps and strategies used. 3. Work through practice problems independently. 4. Compare solutions with a partner.
Materials Needed
  • Notebook
  • Calculator (if needed)
  • Graph paper
Practice Problems
1

Round 47 to the nearest 10.

Hint: Is 47 closer to 40 or 50? Look at the ones digit.
2

Round 834 to the nearest 100.

Hint: Look at the tens digit (3). Is it 5 or more?
3

Round 3,762 to the nearest 1,000.

Hint: Look at the hundreds digit (7). 5 or more? Round up.

Teaching Tip

For this age group: Balance direct instruction with collaborative activities. Allow students to explain their thinking and make connections to prior knowledge when exploring round to nearest 10, 100, and 1000.

AI Tutor

Get instant help with this lesson. Ask questions and receive personalized explanations from your AI tutor.