Many Ways to Show a Decimal

Play Kid Decimals. Have ten students stand in front of the class to represent one set of ten students. Choose a mix of students that can represent various decimal fractions. See examples below:

• Half (0.5) of the students are boys and half are girls.
• Four-tenths of the students are wearing glasses.
• Six-tenths of the students are wearing blue.
• One-tenth are wearing sweaters.
• Three-tenths are wearing sweatpants.

Point out that the set of ten students represents one whole group. Tell the class that you are going to write incomplete sentences on the board that describe parts of the whole group. Challenge students to work with a partner to complete the sentences. Write prompts similar to those below. Note that they use different representations of decimals.

1. Five out of ten students are ______________.
2. 0.4 of the whole group are ______________.
3. One-tenth of the students are ______________.
4. 2/10 of the students are ________________.

When partners have completed the sentences, discuss them with the ten students standing in front of the class. Have volunteers fill in the display of the Kid Decimals Chart Master following the example in Figure 1. Students may see different possibilities for fractions that can complete the sentences correctly. To continue the discussion, ask questions similar to those below. The sample responses use the examples above.

Arrange the students in front of the class to show that both 5/10 and 1/2 represent the fraction that are boys. Have the girls stand together in a group and the boys stand together. Students can say, “Half of the group is boys and half is girls. Five out of the ten students in the group are boys.” Alternatively, have the girls and boys pair off. Students can say, “One out of every two students, or one-half of the group, are boys.”

Play Kid Decimals with a Partner. Have students work with partners to complete Questions 1–3 in the Student Guide. As students answer Question 1, check to see that they use place value in their responses. Students should be able to articulate that the 4 in the place to the right of the decimal is in the tenths place, so it represents four-tenths.

Question 2 reviews the function of the numerator and denominator in common fractions. Students complete a table similar to the class table in Figure 1 to complete Question 3.