Most people know what size they wear. And when they grow out of old
clothes, they just buy the next larger size. But where do sizes come
from? In this lesson, students will use measurement to determine how to
choose sizes when ordering from a catalog, and to investigate if
clothing sizes are standard throughout the United States and the world.
Read the book Jim and the Beanstalk by Raymond Briggs, a variation of the familiar Jack and the Beanstalk.
In this amusing story, Jim helps the giant by measuring him for new
glasses, teeth, and hair. After the story, ask, "How many of you know
what size clothing you wear?" Allow a brief sharing of information, and
then let students know they will be learning about where sizes come
In pairs, have students record estimates of their heights, chests, waists, and hips on the My Own Measurements Activity Sheet.
My Own Measurements Activity Sheet
Then, have students use measuring tapes to find the actual
measurements. Prior to doing so, however, you may want to discuss how
to measure. For instance, lead students to suggest that height is best
measured if the person is standing barefoot against a wall. Further,
you may need to explain that chest measurements are taken under the
armpits, around the highest part of the chest and across the shoulder
blades. (Note that older students may be uncomfortable measuring each
other. As a modification, this activity can be done using lower grade
buddy classes, so that a much younger student is paired with an older
student. Another alternative is to omit chest measurements from this
activity or substitute a different measurement, such as feet or head.)
The image to the right shows that the waist should be measured by
placing a tape measure around the midsection so it crosses in front of
the belly button.
Students should record their measurements on the activity
sheet. Have students compare their estimates to the actual
measurements, and then have them compare their actual measurements to a
sizing chart. You may also want to have students compare their
measurements to charts they find in mail order catalogs or on web
sites. Most online retailers have online sizing charts. An interesting discussion may result
from comparing sizing charts, as different companies often use
(To avoid interruptions during the lesson,
be sure to preview any sites before using them in the classroom.)
Circulate as students are working, assisting and redirecting if necessary. Ask the following questions:
- What are you finding out about clothing sizes? About your size?
- What problems are you encountering?
When at least half the class has completed and recorded their
measurements, gather the whole group together. Explain that they will
have six minutes to work with a different partner to compare their
data. (Students will likely do this anyway, so it’s good to schedule
time for it during the lesson.) As students discuss, they should look
for similarities and differences, and they should share any insights
they had during the activity. You may wish to model this by having a
discussion about measurements with one student while the whole class
Should students finish before six minutes have passed, they can
find a new partner and repeat the task. During student discussions,
circulate and take anecdotal notes about which students are interested,
on-task, and participating at a high level.
Again convene the whole group. Allow students to share their thoughts, especially around the following questions:
- What patterns exist in the sizing charts?
- Who had measurements that fit two or more sizes within a chart? What should that person do if ordering from a company?
- Do you think these numbers are standard throughout the
country? Do you think they are the same from store to store? What about
in other countries?
- Why do you think that some companies number their clothing sizes while others use words like small, medium, and large?
To conclude the lesson, distribute the Clothing Sizes Activity Sheet.
Clothing Sizes Activity Sheet
Students can work on the activity sheet during class, or they
can complete it as homework. Alternatively, you can have students
complete one of the activities listed in the Assessment Options section.
Briggs, Raymond. Jim and the Beanstalk. New York, NY: Paper Star Books, 1970.
- As you circulate while students are working, take note of the following:
- Were students using tape measures accurately?
- Were the students able to use the data on the charts?
- Were the students able to identify the correct location on the charts?
- During a group discussion, have students share their
data and any problems they encountered. Students in the "audience" can
use a non-verbal signal (such as the American Sign Language sign for
"me, too") to indicate when they had a similar problem. This encourages
active listening, provides the teacher with useful information, and
reduces repetition of information.
- Have students answer the questions on the My Own Measurements and Clothing Sizes Activity Sheets. This can be a written assignment or an informal math conversation.
Have all students respond to one of the following prompts in writing:
This lesson was a plus because ____________.
This lesson was a minus because ____________.
This lesson was interesting because ____________.
- Allow students to estimate and measure to find their sizes for hats, gloves, belts, rings, shoes, and other items. Use the Other Sizes Activity Sheet.
Other Sizes Activity Sheet
- Find the range, mean, median, and mode of the class for a particular measurement such as hat size or foot length.
- Invite a guest speaker from a retail store or tailoring shop to discuss measurement and sizes.
- Have students go online to find what their sizes would
be in another country. What is the relationship between sizes in the
United States and in other countries?
- Have students take their measurements again, but this
time using metric units. Then, have them find their sizes using charts
with metric units. What differences do the students notice in measuring
and in finding their sizes on the charts?
Questions for Students
1. What patterns exist in the sizing charts? Share your findings with the whole group.
[As measurements go up, sizes go up. But it’s not proportional. For instance, girls size increases from 8 to 10 with a 3" increase in height; but from size 12 to 14, it’s only a 2" increase in height.]
2. Who fit the size exactly? Who had measurements that fit two or more sizes? What should those shoppers do? Why?
[Shoppers who have different sizes for different categories should probably use the larger size when placing an order. For instance, if a boy is size 10 by height but size 12 by chest, then he should probably order size 12; if he orders size 10, then the item may fit him for height but it will be tight across the chest.]
3. Do you think these numbers are standard throughout the country? Across different stores? Across different brands of clothing? In other countries? Why do you think that?
[Some other countries probably use metric measurements, so it’s unlikely that sizes are standardized. From store to store, it seems unlikely, too, from personal experience.]
4. Why do you think that some companies number their clothing sizes while others use words like small, medium, and large?
[Answers will vary.]
- What were ways the students demonstrated they were actively engaged in the lesson?
- How did your lesson address various learning styles?
- How did the students demonstrate understanding of the materials presented?
- Measure height, chest, waist, and hip.
- Compare their measurements to sizing charts found in catalogs.
- Explain how to choose a size when measurements do not match sizing charts exactly.
NCTM Standards and Expectations
- Understand that measurements are approximations and how differences in units affect precision.
- Select and apply appropriate standard units and tools to measure length, area, volume, weight, time,
Common Core State Standards – Mathematics
Grade 3, Measurement & Data
Generate measurement data by measuring lengths using rulers marked with halves and fourths of an inch. Show the data by making a line plot, where the horizontal scale is marked off in appropriate units-- whole numbers, halves, or quarters.