healthcare professionals across many years has increased the
decline continued though
gap between the number of people who develop cancer and the
2008, according to a recent
number of people who die from it, and ask your students what
report by researchers at the
factors they think are contributing to this increased gap.
same organizations. Point
Students will likely answer that it is the result of increased prevention,
out that this provides
earlier detection, and improved treatment.
evidence that cancer
research has paid off in
3. Invite the students who are still standing to sit, then ask the class
thousands of human lives
whether there is any way to know who will develop cancer and when.
saved. Suggest that some
students may want to
Students may answer that there is no way to know for sure, but, in
consider a career in research.
general, old people, people who smoke, and people exposed to excessive
radiation develop cancer. Accept all reasonable answers without
comment; the purpose of this questioning is to encourage students
to express what they already know about cancer and to highlight the
fact that there is no definitive way to know who will develop cancer. If
students make questionable claims about risk factors or other aspects
of cancer, you may wish to respond that many claims are made about
cancer and then ask students how they could investigate such claims.
You may also wish to point out that Lesson 4, Evaluating Claims about
Cancer, addresses this question.
54
4. Explain that in this lesson, students will learn more about who develops
cancer, when, and why, by assuming the identities of 30 [insert the
number of students in your class] fictitious people who develop cancer
and building a profile of some of the key events in these people’s lives.
Current statistics indicate that 41 percent, or 2 in 5, Americans
will develop invasive cancer during their lifetimes. In this activity,
however, each of the 30 fictitious people develops cancer. The activity
is structured in this way to offer all students similar experiences and
to provide maximum richness and variety to the stories of cancer the
students encounter. Students will be reminded of the 41 percent, or 2 in
5, risk of developing invasive cancer when they complete the questions
on the bottom of Master 1.3, Drawing Conclusions (see Step 18).
5. Direct the students to organize into groups based on the number they
received during the count-off (all students with number 1 should form
a group and so on).
Students will work in groups of four to five throughout the activities in
the module. To ensure that students working together as members of one
group have a common foundation of experience and understanding, we
recommend that you keep students in the same groups for all the activities.
6. Give each student one identity envelope and explain that the outside
of the envelope contains a description of the person that student is
to become. Ask students to read the descriptions on the envelopes
they receive and share who they are with the other members of their
groups. Ask students not to open their envelopes at this time.
We suggest that you do not try to match male students with male names
and female students with female names. Instead, distribute the envelopes
randomly throughout the class. This strategy simplifies the process of
distributing the envelopes and avoids the problem that your class may contain
a different number of males and females than the identity envelopes do.
To make the activity fun, encourage students to read the description
of the person they have “become” to themselves, then introduce
themselves (in first person) to the other members of their group. As
students move through the activity, encourage them to “tell” their
stories to the rest of the group, using first-person language and
representing the person they have become as realistically as they can.
Tip from the field test. Before distributing the envelopes, you may wish
to explain that some students will be asked to assume the identities of
people quite different from themselves (for example, a different sex or
ethnic or cultural group). Explain that this is an inevitable consequence
of the activity’s structure, and ask all students to do the best job they
can representing the people whose identities they have assumed.
7. While students are discussing their new identities, distribute one copy
of Master 1.2, Group Summary, to each student.
55
Student Lesson 1
Cell Biology and Cancer
8. Explain that the students’ task in the next few minutes will be to use
Master 1.2 to summarize information about the lives of the fictitious
people in their group. Point out that the descriptions they just read
contained information about whether each person had a history of
cancer in his or her family. Ask students to use this information to
complete Section 1, Family History, on Master 1.2.
Give the students 1 to 2 minutes to complete this task. If necessary,
explain that having a “history of cancer in the family” means having a
biological relative (grandparent, parent, sibling, aunt, or uncle) who has
or has had cancer.
9. Explain that inside each envelope is a set of four cards that provide
additional information about each person’s life. Direct students to remove
the cards from their envelopes and place them face down on the desks in
front of them so that the cards are in sequence, with the card labeled
“0–19” years on top and the card labeled “60+ years” on the bottom.
Each student should have four cards. Some of the fictitious people
were “born” in the early 1900s and are “old” enough to be 70 or 80;
others were born much later (for example, in the 1970s or 1980s).
Nevertheless, we have extended these people’s lives to 60+ years, even
though this time stretches well into the 21st century. This approach
allows the activity to illustrate a wide range in choices and healthcare
options across the 20th century. The approach also gives each student a
chance to have four cards and participate to the end of the activity.
10. Invite the students to turn over and read the cards labeled “0–19.”
Give the students a few minutes to share the information they learn
with the other members of their groups, then challenge them to use
this information to complete the “0–19 years” column in Section 2,
Cancer History, of Master 1.2.
To heighten the activity’s drama, do not allow students to read all their
cards at once. Insist that students in each group progress through the
life stages in sequence together.
As students begin to read their cards, they may need help
understanding how to fill in Section 2 of Master 1.2.
11. Instruct students to turn over the rest of their cards in sequence,
share the information the cards contain, then use this information to
complete Section 2 of their Group Summary. Challenge the students to
look for patterns or trends in the data they are collecting and explain
that when the class pools all of its data, the students will be able to
determine the degree to which the patterns they see in their group’s
data also appear in the pooled data.
The black dot that appears on one of the four cards for each person shows
when mutations may have occurred that eventually contributed to the
development of cancer. Some students may ask what this dot represents.
56
Do not explain the dot at this point. Respond that students will discover the dot’s significance at the end of the activity (see Step 16).
12. After the students complete Section 2 of their Group Summary, ask
them if they noticed any choices or other risk factors that may be
related to the cancer people developed. Instruct students to go back
through their cards to identify these factors, then list them in Section
3, Possible Risk Factors, of Master 1.2.
Some of these risk factors are smoking, sun exposure, high-fat diet, early
sexual activity, and genetic predisposition for cancer. A major factor that
is not specifically noted is aging. The explanation for increased incidence of
cancer with aging is explored in Lesson 3, Cancer as a Multistep Process.
13. As the groups complete their summaries, distribute one copy of Master
1.3, Drawing Conclusions from the Faces of Cancer, to each student.
14. Project Master 1.4, Summary Profile of the Faces of Cancer, and explain that you will complete the table as the groups share the information
they have collected. Explain that as you complete each row of the
table, you will give the groups 2 to 3 minutes to discuss and record
a conclusion they can make from the pooled data.
To illustrate, ask each group to report how many people in that
group did and did not have a history of cancer in their families.
Then, ask the students what pattern they see in the pooled data and
what conclusion it leads them to make. Direct students to write their
answers in the space provided on the top half of Master 1.3.
Students should see that some people have a family history of cancer whereas
other people do not. If students have difficulty expressing this idea, ask
them whether the number of “yes” answers (the number of people who did
have a family history of cancer) equals the total number of people who
developed cancer (everyone in the class), and what this discrepancy means.
15. Complete each row of Master 1.4 in turn, first asking groups to share
their data with you, then totaling the data and entering them into the
table. After you complete each row, give the groups time to discuss
and agree on their conclusion and add it to their copies of Master 1.3.
• In the second row, students should see that the number of people who
develop cancer increases with age (that is, the incidence of cancer
increases with age). If students have difficulty expressing this idea,
you may wish to ask a guiding question such as, “What do you notice
about the number of people who develop cancer in each life stage?”
Encourage students to write their conclusion as a statement (for example,
“The number of people who develop cancer increases with age.”).
• In the third row, students should see that cancer can develop in
almost any tissue and organ in the body. They also may note that
some types of cancer are more common than others.
57
Student Lesson 1
Cell Biology and Cancer
You may wish to ask students whether the fact that no one in this
sample developed brain or uterine cancer means no one in the U.S.
population gets this type of cancer. Students should recognize that this
is not true. You also may wish to invite students to suggest other types
of cancer that did not occur in this population and list them under
“other” in the third row of the table.
• In the fourth row, students should see that some people make choices
or experience life events that increase their risk of developing cancer.
Tip from the field test. Students may have difficulty distinguishing factors
that increase risk for cancer from those that do not. If so, ask them how
they could find out about risk factors. You may wish to refer students to
the Web site for the National Cancer Institute as an excellent source for
current and reputable information about cancer ( http://www.nci.nih.gov).
16. Ask whether anyone can suggest what the black dot on each person’s
set of cards might mean. Entertain several answers. If necessary,
explain that these dots represent the period of life during which
mutations may have occurred that eventually contributed to the
development of cancer. Ask the students to discuss in their groups
what they notice about the dots. Explain that students will learn more
about these mutations in Lesson 2.
Give the students several minutes to look at the dots and discuss what
they observe. If students seem to be confused about what they should
be noticing, ask them guiding questions such as, “What do you notice
about the period of life in which each person’s dot occurs and the
period in which that person’s cancer was detected?”
Be sure that students understand the difference between the period of
life in which the mutations associated with the development of cancer
occurred and the period in which the cancer was detected. In some cases,
the dot appears in the same period of life that the cancer was detected.
In most cases, however, the dot appears many years before that period.
17. Ask two or three groups to report what they observed about the dots and
initiate a class discussion about the significance of these observations.
Help students understand that cancer develops across time and often
many years intervene between the first cancerous changes and the
symptoms that cause a person to seek medical help.
As part of this discussion, you may also wish to ask students
• what factors in people’s lives improve their chance of recovering
from cancer (for example, early detection and treatment);
• what factors reduce their chances of early detection (for example,
poor access to health care, either because of where they live or
their socioeconomic status); and
• what factors increase their chances of early detection (for example,
participation in opportunities to be screened for cancer)?
58
Challenge students to support their answers by referring to specific
people they learned about in this activity.
18. Close the activity by asking students to complete the Discussion
Questions on the bottom of Master 1.3 either in class or as homework.
Briefly discuss their answers with them at the end of the period or at
the beginning of the next.
Collect and review the
Question 1. In this activity, all students in the class assumed the role of
students’ completed
someone who developed cancer sometime in his or her lifetime. Is this
worksheets to assess
an accurate representation of the risk of cancer among the American
their understanding
population? Explain your answer.
of the lesson’s
major concepts.
No, this is not an accurate representation. Students should remember
the opening exercise in which they learned that current statistics
indicate that 41 percent, or 2 in 5, of Americans develop invasive cancer
sometime in their lines. Point out that in this activity, students studied
30 people who all got cancer, but this does not mean that everyone will
get cancer in his or her lifetime.
Point out as well that students should not extrapolate from the rates of
cancer illustrated in the activity. Although the general trends illustrated
in these 30 people are accurate (for example, rates for lung, colon, and
breast cancer are higher than rates for cervical, pancreatic, and ovarian
cancer), rates for other cancers are artificially exaggerated as a result of
the small sample size. A striking example of this exaggeration occurs
in the case of retinoblastoma. We included retinoblastoma to illustrate
an example of a hereditary cancer, even though its incidence in the U.S.
population is less than 1 in 1 million per year.
Question 2. What explanation can you offer for the observation you made
about the incidence of cancer compared with age?
Answers will vary. Some students may suggest that it is related to the
fact that cancer develops across time (which they learned when you
Asking students to name the
discussed the black dots with them). Because older people have lived
most important thing they
longer, they have a greater chance of developing it. Students will return
learned challenges them to
to this question in Lesson 3, Cancer as a Multistep Process.
identify the lesson’s key
ideas. If students have
Question 3. What is the most interesting or surprising thing you learned
difficulty with this, ask
from this activity? What is the most important? Why?
questions based on the
objectives in At a Glance.
Answers will vary.
Extend or enrich this activity by asking students to bring to class current
Potential
newspaper or magazine articles about cancer. Display these in your classroom
Extensions
and, at the close of Lesson 5, invite students to comment on them, drawing
on what they learned about cancer during the preceding lessons.
59
Student Lesson 1
Cell Biology and Cancer
Lesson 1 Organizer
What the Teacher Does
Page and Step
Ask students to count off in sets of 6 (1, 2, 3, 4, 5, 6, 1, 2, etc.) and
Page 53
remember their number.
Step 1
Explain that statistics are often used to characterize large populations.
Page 53
In this activity, the classroom represents the U.S. population.
Step 2
• Ask students with numbers 2, 3, 5, or 6 to stand. This represents the
4 of 6 people in the U.S. who will have children. Ask students to sit.
• Ask students with numbers 3 or 6 to stand. This represents the 2
in 6 people who will be involved in an alcohol-related automobile
accident sometime in their lifetimes. Ask students to sit.
• Ask students with numbers 1 or 4 to stand. Explain that about 2
in 6 people in the room will develop cancer sometime during their
lifetimes.
• Ask about one-fourth of the standing students to sit.
• The number of students left standing represents the approximate
percentage of the U.S. population that will die of cancer (about
25 percent).
• Tell students that the work of scientists and health professionals has
increased the gap between the number of people diagnosed with
cancer and the number who die from it.
• Ask students what factors have contributed to this increased gap.
Have all students sit. Ask the class if there is any way to know who will Page 54
develop cancer and when.
Step 3
Inform students that in this activity they will learn more about who
Page 55
develops cancer, when, and why by assuming the identities of fictitious Steps 4
people. Have students to organize into groups according to their
and 5
numbers from Step 1.
Give each student one identity envelope. Explain that the outside of
Page 56
the envelope contains a description of the person that student will
Step 6
become. Ask students
• to read the descriptions on the envelope,
• to share that information with other group members, and
• not to open their envelopes.
60
What the Teacher Does
Page and Step
Give one copy of Master 1.2 to each student and ask groups to
Page 55
complete Section 1.
Steps 7
and 8
Direct students to remove cards from envelopes and place them face
Page 56
down on their desks so that cards are in sequence, with the card
Step 9
labeled “0–19 years” on top.
Ask students to turn over and read cards labeled “0–19 years” and
Page 56
to share information with their group members. Instruct groups to
Step 10
complete the “0–19 years” column in Section 2 of Master 1.2.
Instruct students to turn over the rest of their cards in sequence
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and then to complete Section 2 of their group summary. Challenge
Steps 11
students to look for patterns in the data and to list possible risk factors and 12
in Section 3 of Master 1.2.
Give each student one copy of Master 1.3 and project Master 1.4.
Page 57
Explain that you will complete the table as groups share information
Steps
they have collected. For each row completed, give groups 2–3 minutes
13–15
to discuss and record a conclusion (such as patterns) they can make
from the pooled data. Direct students to write their answers on their
copies of Master 1.3.
Ask for suggestions about what the black dot on each person’s set
Page 58
of cards might mean. (The dot represents when mutations that
Step 16
contributed to the development of cancer may have occurred.) Ask
students to discuss what they notice about the dots.
Ask a few groups to report what they observed about the dots and
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discuss the significance of these observations as a class.
Step 17
Close by asking students to complete the discussion questions on
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Master 1.3. Briefly discuss answers.
Step 18
= Involves copying a master.
= Involves making a transparency.
61
Student Lesson 1
L E S S O N 2
Explore/Explain
Cancer and
the Cell Cycle
Focus
At a Glance
Students start by reviewing four historical observations about agents that