Student Goal

I can work with decimals and explain the value of each digit.

Why It Matters

Decimals help students make sense of money, measurement, data, and real-world quantities.

Warm-Up

Warm-Up 1

In 4.73, what digit is in the tenths place?

Warm-Up 2

Which is greater: 2.08 or 2.8?

Warm-Up 3

Round 6.47 to the nearest whole number.

Short Lesson

Standard Focus:

NC.6.NS: The Number System

Student-Friendly Standard Goal:

I can use decimal place value to compare, round, add, and subtract decimals.

  • Decimals are built on place value. The first place after the decimal is tenths, then hundredths, then thousandths.
  • When comparing decimals, line up the decimal points. You can add zeros at the end to make numbers easier to compare.
  • For decimal addition and subtraction, line up decimal points so each place value stays in the correct column.

Guided Examples

Guided Example 1

Add Decimal Money

A notebook costs 2.75 dollars and a pencil costs 0.85 dollars. How much do they cost together?

Step 1

2.75 + 0.85

What should line up before adding?

Guided Example 2

Compare Decimals

Which is greater: 5.9 or 5.19?

Step 1

5.9 = 5.90

Why can we write 5.9 as 5.90?

Practice

Problem 1

Which number is greatest?

Problem 2

Round 8.63 to the nearest whole number.

Problem 3

Find 4.25 + 1.7.

Problem 4

True or false: 2.8 is greater than 2.08.

Problem 5

A bottle holds 1.5 liters. How many liters are in 4 bottles?

Reflection

How are you feeling about today's skill?

Optional reflection: Optional prompt: Where do decimals show up in real life?