## Hands vs. Feet

### Melanie HendersonBay District Schools

#### Description

Students use unconventional units of measurement to discover the importance and need for a uniform unit of measurement.

#### Objectives

The student understands the need for a uniform unit of measure to communicate in real-world situations.

#### Materials

-Construction paper
-Pencils
-Scissors
-Rulers
-Math journals
-A list of things to be measured

#### Preparations

Teacher just needs to have materials ready and a list of objects that is to be measured on the board.
1. Gather materials.
2. Determine objects to be measured. Choose objects that will yield easy measurements, such as 1 foot, 6 inches.
3. Write questions on the board or on an overhead.

#### Procedures

1. Introduce this lesson by telling students: I want all of you to pretend that we live in a world that has no rulers. There is absolutely no uniform or consistent way of measuring things. I want to know how long our classroom is. If I do not have a ruler, how can I measure it? ( most responses will be to use an object or a body part)

2. Respond to students: Those are all great ideas! Would you like to help? Great! I want all you of you to trace your hand on the construction paper. Then, cut it out and use your paper hand to measure all things listed on the board. (The list can include any 5-10 objects in the classroom as well as the length of the classroom.) Record each object and its 'hand' measurement in your math journals. Are there any questions? Begin. (These directions may need to be repeated until each student understands.) As students are measuring, circulate and observe but do not give advice or help.

3. After about 20 minutes, gather students into a large group and ask for the results and record the different 'hand' measurements on the board. Call on several different students, so that the kids can see that the measurements are different.

4. Write these two questions on the board: Why are the measurements different when everyone measured the same things? ( Everyone has different size hands; hence, different measurements.) How could we get everyone to have the same measurements? (Have everybody use the same unit of measurement.)
-Students should answer all questions in their journals first. Then, allow them to share the answers.

5. Tell children: Let's try measuring the same objects, only this time, let's use the rulers and measure using feet and inches as the unit of measurement. (Allow time for students to look at the ruler. Discuss feet and inches. Have students practice measuring their desktops. Model how to write the feet and inches on the board.)

6 Tell students to re-measure the objects and record the new measurement beside the 'hand' measurement in the math journal.

7. After about 10 minutes, gather back into a large group. Ask for the results. (All results should be the same or very close.) Ask: Why did we all get the same answers? (Used the same unit of measurement.)

8. Write this question on the board and ask students to respond to it in their journals: Why is it important for everyone to use a standard or the same unit of measurement, instead of whatever you have? (If you don't use a standard unit of measurement, nobody else will know -how much- or -how far- you have measured.)

#### Assessments

Since this is an introduction lesson to units of measurement, students will be formatively assessed by their journal entries. Through the activity students should discover on their own that it is necessary for everyone to use the same unit when measuring and student should justify their reasoning with plausible examples. With this information, future instruction can be planned to meet student needs.

#### Extensions

-Try measuring with different objects, such as a pencil, chairs, desks, etc.