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Eggheads: Pioneers of genetics
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vocabulary, writing skills, and oral
language development.
The requirements for the geneticist’s full biography include:
•
•
•
•
Vital statistics
Educational history
Major discovery
Accomplishments, publications,
or recognition
• State of technology during
his/her time period
• Collaborations with other
scientists
• Reception/acceptance of discovery at time period
• Connection of discovery to previous
and impact for future scientists
• Quote or primary source information Renowned egghead
Victor Fleming
Additionally, students should answer the following questions:
• Do the discoveries of the scientist still hold true today?
• Did the scientist make any major mistakes or bad decisions?
• Could the scientist have made their discovery without the
use of technology?
• What makes this scientist special or interesting?
• Three adjectives that would sum up this scientist.
• How did this scientist’s discovery shape or change genetic
understanding?
• How does each scientist’s work contribute to the progression of scientific events?
• What technology was available for each of the scientists?
• How have advancements in technology contributed to the
development of scientific knowledge?
• What was considered “scientific fact” during the time
period of your scientist?
• How have the “scientific facts” changed with new
discoveries?
Encourage students to use primary source materials such as letters, diaries, or newspaper accounts and secondary source materials
such as other biographies, reference books, or histories. Students
Sandy Buczynski (sandyb@sandiego.edu) is an assistant professor
at the University of San Diego in San Diego, California.
PHOTO COURTESY OF THE AUTHOR
The pioneer men and women of genetics, from different countries, their work spanning a period of more than 100 years, have
collectively carved a path for genetic advancement. Creating a
genetic timeline of these discoveries enables students to view
the historical perspective of genetic innovation and to associate
these findings with individual scientists. In putting a genetic
timeline in order, the impact of biotechnology on the progress
of scientific discoveries becomes evident. Students realize that a
genetic research timeline is more of a ladder than a line because
scientists build from the discoveries of those before them.
This “egghead” activity takes a personal approach to developing a genetic timeline. A list of suggested geneticists and a sample
timeline (see Figure 1) are provided so that each student can
select one genetic pioneer to research. (Hint: Make sure students
select scientists from along the full range of the genetic timeline.)
In the library or resource center, students need one class period
to gather data about their scientist’s discovery, biography, and
to obtain a photo (digital image) of the scientist. Once the preliminary research is complete, students will begin construction
of an egghead likeness of the scientist. This can be done at home
or in class. If performed as a class project, the only cost for this
activity is the price of eggs. It is best if the teacher provides the
raw eggs rather than having students attempt to bring a raw egg
from home. The rest of the supplies for the project, students can
provide from materials on hand. These materials include half
a shoebox for the diorama, cardboard for egg collar, construction paper, felt or cloth for clothing, yarn for hair, bits of clay,
colored markers and pencils for facial expression, and any props
to be used to illustrate the scientist’s accomplishment. Eggs can
be blown out one day (allow about 15 minutes of class time),
washed thoroughly, and left to dry overnight. The next day, a full
class period is needed for eggheads to be illustrated and dioramas
constructed. Oral presentations and extension activities follow,
providing a platform for students to share their understanding
of the progress scientists have made in the field of genetics.
In constructing a biography of their geneticist, students write a
two page comprehensive paper using the following requirements
and then summarize this biography on an index card which is
attached to the collar of the egghead. The full biography should
analyze and interpret the events in the scientist’s life and make
an argument about the significance of the scientist’s accomplishments. The biography also highlights any technology in
existence during the lifetime of the scientist. This can be done
as an interdisciplinary collaboration to integrate and reinforce
an English assignment or as a science literacy activity to build
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should be objective and avoid burying the scientist’s failures.
Have students cross-reference the facts, especially online sources,
to make sure of accuracy and create a documented source list.
In addition to the biography, students create a likeness of
their scientist using an empty eggshell (see Making an egghead).
After sketching in the main features of the face on a hollowed
out egg, craft materials are used to highlight expression, create
features, glasses, period costumes, etc. If you choose, the egghead
can be placed in a shoebox diorama. The diorama illustrates the
significant discovery made by the scientist. For example, Gregor
Mendel placed in a pea garden or James Watson placed next to a
model of DNA. Or, the scientific discovery can be illustrated on
the back of the index card summary of the scientist’s biography.
If the diorama is constructed in half a shoebox, the egghead
projects can be stacked in the classroom for easy storage and
viewing. Be sure all eggs have been thoroughly washed with
soap to prevent any smell or safety concerns.
Once the eggheads are constructed, students present their
egghead scientist’s bio and genetic discovery to the class in the
chronological order of the genetic timeline. Each presentation is approximately five minutes, giving just the highlights
of the scientist’s accomplishment. The students use their
index card bio summary for the presentation, which includes
the scientist’s name and background; brief explanation of
major discovery; high points/low points of scientist’s career;
important technology used for this genetic breakthrough;
and any other memorable information about scientist. In
giving an oral presentation, students need to remember to
be accurate, confident, and enthusiastic with their scientist’s
biography and discovery. As the presentations are completed,
the eggheads can be lined up in chronological order allowing
students to view the entire progress of genetic discoveries.
Extensions
Once the eggheads are complete, they can be used as teaching
tools for the following activities:
• Scrambled eggheads: Place your order—Put all the geneticist
eggheads in a pile. In order to create a chronological order
or genetic timeline-up, select a single scientist egghead as a
starting point. Now, select another scientist egghead from
the pile. Would this next scientist egghead be placed before
or after the starting point egghead? Select another egghead
from the pile. Does the scientist just picked go between the
two scientists already in the line-up? Before one? After the
other? As each egghead is selected from the pile, the timeline
grows. The placement of each subsequent egghead becomes
more difficult as students must now decide if the chosen sci-
Making an egghead
Materials
• Raw egg
• Straight pin (darning needle, corsage pin)
• Cardboard or cardstock, about 8 cm wide and 13 cm long
• Glue
• Decorating items (colored pencils, bits of yarn, wire,
cloth, felt, thread, cotton, modeling clay, tissue paper,
construction paper, string, etc.)
• Index card
Procedure
1. Wash the raw egg with soap and water and bring the egg
to room temperature for easier extraction of contents.
2. Using a straight pin, make a hole in one end of the egg,
pushing the pin far enough into the egg to break the yolk.
Enlarge the hole by rotating the pin. (Hint: This hole will
not be seen because the collar will cover it.)
3. Make another hole in the opposite end of the egg. This
hole can be smaller.
4. Blow gently through the small hole in the egg with the larger
hole of the egg facing down into a clean bowl. Safety Note:
Be sure to avoid getting the raw egg in your mouth!
5. Once the contents are out of the egg, clean the inside by
adding a bit of liquid soap into the large hole and holding
the shell under running water with the large-hole side
up. Turn egg over and let water drain from large hole.
Repeat. Set empty eggshell with large hole down and
let dry overnight.
6. Make a small cylinder to serve as an egg collar out of
cardboard. Staple ends closed and use a thin bead of
glue to secure eggshell into collar. This serves to steady
the egg while you work. (Hint: If the collar is too large,
the scientist loses his/her neckline.)
7. Create a likeness of your scientist. After pencil sketching
in the main features of the face, tissue paper or modeling
clay can be used to create noses, ears, and facial texture.
Yarn, raffia, fiber, cotton, or thread can be for hair and twist
ties for glasses. (Hint: Digital likenesses of geneticists can
also be contoured using photo software and then glued
to the egghead for more accurate depictions.)
8. Summarize the main biographical elements of your scientist
on an index card that will be attached to the egghead.
9. Punch a hole at the bottom of the cardboard collar. With
a length of string, attach the biography index card to
the egghead.
entist belongs in the future or in the past of scientists already
in the timeline-up. To simplify, this exercise can also be done
in “chunks” of timeline (e.g. from 1850–1900)
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FIGURE 1
36
Suggestions for genetic timeline
Date
Scientist
Discovery
1859
Charles Darwin
Wrote: On the Origin of Species by Means of Natural Selection
1865
Gregor Mendel
Heredity transmitted in units
1869
Frederick Miescher
DNA isolated
1879
Walter Flemming
Mitosis described
1900
DeVries, Correns, and von Tschermak
Independently rediscover Mendel’s work while doing their own work
on the laws of inheritance
1902
Walter Sutton
Chromosome theory of inheritance
1902
Archibald Garrod
Orderly inheritance of disease
1909
Wilhelm Johannsen
The word gene is coined
1911
Thomas Hunt Morgan
Chromosomes carry genes (fruit flies)
1941
George Beadle and Edward Tatum
One gene, one enzyme hypothesis
1943
William Astbury
DNA has a regular periodic structure
1944
Oswald Avery, Colin MacLeod, and
Maclyn McCarty
DNA transforms cells
1944
Barbara McClintock
Jumping genes
1952
Alfred Hershey & Martha Chase
Genes are made of DNA
1953
Francis H. Crick and James D. Watson
(younger)
DNA double helix
1955
Joe Hin Tjio
46 human chromosomes
1955
Arthur Kornberg
DNA copying enzyme
1958
Matthew Meselson and Franklin Stahl
Semiconservative replication of DNA
1959
Jerome Lejeune
Chromosome abnormalities identified (trisomy 21)
1961
Robert Guthrie
First screen for metabolic defect in newborns (PKU)
1961
Sydney Brenner, François Jacob and
Matthew Meselson
mRNA ferries information
1966
Marshall Nirenberg
Genetic code cracked
1975
Frederick Sanger
DNA sequencing
1978
David Botstein
DNA polymorphism (RFLP’s)
1980
Kary Mullis
polymerase chain reaction (PCR)
1984
Alec Jeffreys
DNA fingerprinting
1989
James Watson (older)
Heads National Center for Human Genome Research
1992
Daniel Cohen
Map that includes genetic markers on all 23 human chromosomes
1993
Allen Roses
Major susceptibility gene for the late-onset form of Alzheimer Disease
1997
Dollie & Bonnie
Researchers at Scotland’s Roslin Institute report cloning a sheep
2000
The Human Genome Project
A rough draft of the human genome is completed
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FIGURE 2
Rubric
Novice egghead
Informed egghead
Accomplished
egghead
Master egghead
Construction
of egghead
Work on adding
features to eggshell
that would make it
more closely
resemble scientist.
If viewed from certain
angle, egghead
resembles the
chosen scientist.
Egghead gives an
impression of the
scientist. Added
features help with
scientist’s recognition.
Egghead is well
constructed and
actually looks like
the scientist.
Oral
presentation
Work on speaking
voice, and creating
audience interest in
your scientist.
Try to make eye
contact with audience
and be expressive
and comprehensive
with information about
scientist.
Clear articulation and
good use of information
about scientist to
enlighten audience.
Confident with scientist
and discovery.
Articulate, engaged
audience, and
enthusiastic.
Written
biography
Work on paraphrasing,
grammar and spelling.
Reread required
components of
biography and add
material where needed.
Consider the “think
about” section
of the biography
requirements. This type
of information adds
depth to the biography.
Consistent and
engaging style
throughout narrative
with few errors in
mechanics, content,
or facts.
Narrative is original.
Grammar and spelling
are flawless and the
flow provides a logical
pathway of ideas.
Genetic
timeline-up
participation
Try to be more active in
discussion of scientist’s
placement in the
timeline and in making
connections between
scientists.
Can place own scientist
in timeline and “gets”
those connections that
others make.
Makes connections of
various scientists on
own. Contributes ideas
and initiates action.
Understands place and
contribution of own
scientist in overall task.
Extends connection to
other scientists past
and future.
• Absent Eggheads: Missing reaction—Line the eggheads
up in chronological order. Now remove a single egghead
scientist. Students write in their journals how they think
the absence of this particular scientist’s discovery might
impact the future of the timeline. Prompts might include:
Would future genetic discoveries take longer? How have
“scientific facts” from the time period of the missing egghead scientist changed with new discoveries? Would the
technology necessary for future discoveries be missing?
Would this egghead scientist not be missed at all?
• Egghead Bloopers—Some genetic scientists received
little reaction from the scientific community of their time
period. Others made public missteps or mistakes. What
about your scientist? Write a single paragraph revealing
any blooper in your scientist’s background.
Concluding the egghead activity
Students are assessed on this activity in four ways—the actual
construction of the egghead, the written biography, the oral
presentation, and interaction with classmates on the role of
their scientist in the chronological timeline (see Figure 2).
Today, scientific discoveries can feel anonymous to students.
We take many of breakthrough discoveries for granted in the
present day. We teach students the structure of DNA as fact.
However, back in the 1950s, we had no idea what the configuration of DNA looked like. This timeline activity was created to
renew the notion that individual actions make a difference in the
progress of scientific thought. It is important to tell the pioneer
scientists’ stories over and over again. As scientific discoveries
become more nameless in the twenty-first century, it is valuable
to create a connection between a person and the impact their
discovery had in advancing the field of genetics.
Resources
Genetic timeline—www.genome.gov/10506099
History of genetics timeline—www.accessexcellence.org/AE/AEPC/
WWC/1994/geneticstln.html
History of genetic testing—www.acad.swarthmore.edu/bio5/tong/
Gene%20Basics/the_history_of_gene_testin.htm
Portraits of scientists timeline—genetics.gsk.com/history.htm
DNA from the beginning—www.dnalc.org/home.html
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Caring about
karyotyping
FIGURE 1
When investigating genetics and
inheritance, middle school students are
usually asked to look at cells, genes, and
DNA. They investigate how the cell
functions as well as how mutations can
occur through errors in the “misspelling”
of genes when DNA is copied. While
good investigations, these activities
do not address large-scale mutations
that occur at the chromosome level.
Errors that occur during meiosis and
gamete production (sexual reproduction)
can lead to important chromosomal
abnormalities such as Trisomy 13.
The following activity illustrates how
students, with the leadership of a local
university, can take on the role of genetic
technicians in a hospital as they explored
mutations at the chromosome level.
Looking at real world applications of
genetics research and technology helps students understand
some of the many reasons why science is important.
Getting ready
Setup for this activity is relatively simple, taking only
about 30 minutes or so to make copies, assemble fictitious
patient files, cut out chromosomes to complete karyotypes,
and make overhead transparencies to facilitate discussions.
Make nine copies of the partially completed karyotypes
(Figure 1), one for each group of 3–4 students. Glue one
copy into each manila folder and label them “Patient
A” through “Patient I” (see Figure 2). These are folders
students will use to analyze their patient’s chromosomes
for abnormalities.
Make copies of the chromosomes that are used to
complete patient karyotypes (Figure 5). Specifically, you will
need nine copies of chromosomes 1–22 , two extra copies of
chromosome 21, two extra copies of chromosome 13, five X
chromosomes, and five Y chromosomes. Carefully cut out
the chromosomes and place them in piles with other like
chromosomes (for example place all copies of chromosome
one together and all the copies of chromosome two together,
etc.) Label your nine standard envelopes “Patient A”
through “Patient I.” Begin placing extra chromosomes
into the standard envelopes using Figure 2 as a guide.
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Partially completed karyotype
Place the manila folders and labeled envelopes (with extra
chromosomes inside) off to the side until students are ready
to begin constructing their karyotypes. You will also need
overheads of Figures 4–6.
To keep things manageable, we broke each class into
nine groups. That gave us groups of three to four students
(depending upon class size). Depending upon the interest
of the students, this activity can last 1–2 days or up to
a week. To be successful in identifying chromosomal
abnormalities, students need only know that chromosomes
are the “books” that hold our genes. They should also be
familiar with the idea that mutations are changes in an
organism’s genetic makeup. We conducted this activity
towards the end of our unit on genetics. Within a learning
cycle context, placing this activity at the end of the unit
provided a real-world avenue for students to apply what
they had earned about mutations. By this time students
understood that mutations, while rare, could be beneficial,
harmful, or neutral to an organism. It also served as a
springboard for students to begin independent research
on their own time, or as a class assignment.
Kirstin Bittel (kirstin.bittel@tusd1.org) is an eighth grade science
teacher at Mansfeld Middle School in Tucson, Arizona. Laura Carsten
is a graduate student in Ecology and Evolutionary Biology at the
University of Arizona, Tucson
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Setting the scene
is missing. Sometimes the organism can survive, other times
it cannot. Either way, these abnormalities in the number
of chromosomes can be detected using karyotyping. We
do not give the students too much more information than
this. However, the University of Arizona has a wonderful
online activity that is well suited to more advanced students
or adults who want to learn more about the process of
karyotyping (see Resources).
Next the class discusses what might cause a genetic disorder
(mutation) and are prompted to review how mutations at the
DNA level occur. This is done through a series of questions
beginning with recall questions about the roles of DNA,
genes, chromosomes, mutations. Then students are asked to
recall the definition of a mutation. Finally, students identify
that small changes in DNA cause mutations. These “spelling
mistakes” in our genetic alphabet can be caused by the body
making a mistake, or by environmental factors like the sun or
expose to cigarette smoke. From there, we review the process
of meiosis using basic readings from the textbook. I do not
expect my middle school level
students to memorize the names of
Chromosomes for patients A through I
each phase, but I do expect them
to remember the basic process
and the reason why sex cells are
Patient condition
haploid (have only 23 individual
Contents of envelope
(for teacher reference only)
chromosomes. If they were diploid
(having 23 pairs of chromosomes,
1 copy of each: chromosomes1–22
Normal female
1 copy of chromosome X
or all 46 individual chromosomes)
1 copy of each: chromosomes1–22
like all other cells in the body,
Normal female
1 copy of chromosome X
then fertilization would cause
1 copy of each: chromosomes1–22
a doubling of chromosomes in
Normal male
1 copy of chromosome Y
the offspring and, after a few
1 copy of each: chromosomes1–22
generations, humans would
Normal male
1 copy of chromosome Y
have too many chromosomes
1 copy of each: chromosomes1–22
to function correctly. Students
1 copy of chromosome X
Female with Trisomy 13
are asked to predict what could
1 extra copy of chromosome 13
possibly go wrong (how mutations
1 copy of each: chromosomes1–22
might occur) at this stage in the
1 copy of chromosome Y
Male with Trisomy 13
creation of haploid reproductive
1 extra copy of chromosome 13
1 copy of each: chromosomes1–22
cells. With a bit of prompting
Female with Trisomy 21
1 copy of chromosome X
and questioning, students come
(Down’s Syndrome)
1 extra copy of chromosome 21
to the conclusion that, as the
1 copy of each: chromosomes1–22
chromosomes are being divided
Male with Trisomy 21
1 copy of chromosome Y
into the egg and sperm cells,
(Down’s Syndrome)
1 extra copy of chromosome 21
they get pulled to the wrong side,
1 copy of each: chromosomes1–22
Male with Klinefelter
leaving some cells with too many
1 copy of chromosome X
Syndrome
chromosomes and others with
1 copy of chromosome Y
too few.
Students are told that they will be assuming the role of a
genetic technician and that their job will be to analyze
a karyotype for a patient to determine if that patient is
healthy or not. This is usually the students’ first exposure to
the word karyotype, so we take some time explaining them.
We tell students that a karyotype is a test used to identify
genetic abnormalities (mutations) within chromosomes.
Chromosomes, which are located in the nucleus of the cell,
store the genetic material that enables cells to carry out all
the functions of a living organism. Scientists take a blood
or bone barrow and grow a tissue culture to ensure that
cell division is occurring. Cells are taken from those tissue
samples and the chromosomes in those cells are stained. Next
the chromosomes are photographed. These photographs can
be cut up and matched to look for genetic abnormalities. In a
normal or healthy person there are 23 pairs of chromosomes
, or 46 total individual chromosomes. If a person has too
many or not enough, information a cell or organism needs
FIGURE 2
Patient letter
(as shown on
envelope)
A
B
C
D
E
F
G
H
I
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Procedures
karyotype and an envelope containing the rest of the
chromosomes that will be used to assemble the karyotype.
Once groups are prepared, they are handed a folder
Their job is to correctly assemble the karyotype and
representing a patient and told that it is their job as the
diagnose their patient. Before students begin work, make
genetic technician to determine both the sex and health of
sure that the normal male karyotype and normal female
the child subject. Inside that folder is a partially completed
karyotype are shown on the
overhead so students see what
Extra chromosomes to complete patient karyotypes
FIGURE 3
they are working towards
(Figures 5 and 6). As students
work, have Figure 4 on the
overhead.
Once groups have
diagnosed their patient, they
are given a blank overhead on
which to write their diagnosis.
If students struggle, ask them
to look at the numbers of
chromosomes. Do they have
two of each or do they have
extras? Remind them to
reference the overhead to assist
them with correctly writing
their diagnosis. Students write
down the number of total
chromosomes, followed by
the sex (XX for female or XY
for male). If their patient has
an abnormality, it is noted
at the end with a plus sign
and the number of the extra
chromosomes (see Figure 4).
Student groups then
take turns going to the
overhead and presenting
their patient’s case to the
class, hypothesizing how
FIGURE 4
40
Chromosomal abnormities
46 XY
46 XX
Normal
No extra or missing chromosomes
Klinefelter Syndrome
One or more extra sex chromosomes (i.e., XXY)
Down’s Syndrome - also called Trisomy 21
Extra chromosome 21
47 XY +21
47 XX +21
Trisomy 13
Extra chromosome 13
47 XY +13
47 XX +13
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47 XXY
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they think the extra chromosome
(if their patient had one) will
affect the patient. At this point,
students do not know anything
about the individual chromosome
or what genes are located on them.
Their hypotheses should only
be expected to state that having
extra information will probably
negatively impact the patient. For
advanced classes, this is a prime time
to journey to the computer lab for
a day or two and conduct research.
Once all groups have presented
their findings and hypotheses, we
(the teachers) discuss each of the
disorders and how common they
are. Klinefelter Syndrome affects
approximately 1 out of every 700
and generally results in infertility
as an adult. A female version of
this disorder, Turner syndrome,
where an X chromosome is missing,
also generally results in infertility.
Down’s Syndrome (also called
Trisomy 21), affects 1 in 10,000
children and results in a variety
of birth defects and severe mental
retardation. Trisomy 13 affects 1
in 5,000 children and results in
multiple abnormalities, many of
which are fatal. After students
have been exposed to these rare,
but potential problems it is a
good idea to move onto the topic
of how genes have developed
mechanisms to prevent mutations
from occurring. We share with
students that the human body
has specific proteins that “spell
check” DNA as it is being copied.
Often mutations are corrected
by this “spell-checking” process.
Depending upon the maturity of
the individuals in each class we also
discuss the reason for miscarriages.
Many students know women who
have miscarried and it reassures
FIGURE 5
Fully completed female karyotype (Normal)
FIGURE 6
Fully completed male karyotype (Normal)
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them to know that, while sad, this is a way the body prevents
humans with severe mutations from being born into a world
they most likely will not survive in.
Assessment
Assessing student performance on this activity requires us to
move throughout the room to constantly evaluate student
progress. Students are evaluated on how well they work
together, as well as how correct their completed karyotype
is. A final piece of assessment comes as we conduct the
post-lab discussion. Students are evaluated on their ability
to correctly identify the disorder or lack of disorder for their
patient, as well as their willingness to hypothesize about
possible repercussions of having an extra chromosome. As
with all other labs, a student or group assessment rubric
could be used.
Conclusion
For more advanced classes, I would suggest using more
accurate chromosome images. These images were great for
the average middle school student population. There are
just enough differences in the images for the activity to be
doable, but enough similarity that the students really had
to work together and think about the banding and location
of the centromeres. Similarly, for more mature classes, you
could include more examples of chromosomal disorders or
invite students to conduct further research on the disorders
diagnosed in the classroom.
My students enjoyed the opportunity to step into the
role of a genetic technician and analyze chromosomes.
They were curious about the disorders but extremely
respectful. It was a good opportunity to encourage students
not only to look into possible disorders that result from
chromosomal abnormalities, but also to teach acceptance
and tolerance.
Acknowledgments
This lesson is adapted from the University of Arizona’s Biology
Project lesson titled “Karyotyping Activity” available online
at www.biology.arizona.edu/human_bio/activities/karyotyping/
karyotyping.html. The chromosome images are from http://oak.
cats.ohiou.edu/~schutte/new_page_1.htm. We wish to extend our
gratitude to Kathie Dosh and Rachel Hughes for their helpful
comments on earlier drafts.
Resources
University of Arizona Biology Project—www.biology.arizona.edu/
human_bio/activities/karyotyping/karyotyping.html
Information about the various disorders—www.nlm.nih.gov/
medlineplus/encyclopedia.html
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Solutions and
dilutions: Mixing the
math into the science
This lab activity teaches students how to make solutions and dilutions while reinforcing the mathematical
concepts involved. The materials used are cost-effective,
readily available, and safe for students to handle. The
activity reinforces the concept of dilutions visually. “I
see know” is a common refrain during this activity as
students compare and contrast their dilutions.
To determine how much tap water and concentrate
(stock solution) will be combined to create the solutions
specified in the activity, students can divide the total volume needed for each solution by its dilution factor (df).
For example, to make a 200 mL solution with a 1:10 dilution, students would divide 200mL (total volume) by 10
(df) to arrive at 20 mL. They would then combine 20 mL
of concentrate (one part) with 180 mL of tap water (nine
parts) to create a 200 mL solution with a 1:10 dilution.
Students came away from the laboratory experience
with a better understanding of solutions and dilutions.
Teachers appreciate this activity because it is low-cost
and easy to assess; they are able to tell at a glance if the
dilutions are correct. As a practical extension, have
students bring in an empty can of concentrated juice or
soup. Have students fill their empty cans with water and
15 drops of food coloring to represent their stock solution
of the soup or juice concentrate. Then, have students
follow the directions on the can to complete the juice or
soup, and calculate the final dilutions of the solutions.
Materials
The materials listed below are for a class of 30 students working in groups of 2–3
• four beakers or flasks (125 mL, 250 mL or larger)
• food coloring (one box will be plenty for the entire class)
• 1 micropipette
• 1 graduated cylinder (50 mL or 100 mL)
• masking tape
• 1 marker
• tap water
Nancy L. Elwess is (nancy.elwess@plattsburgh.edu), and Christopher
Cottrell received his B.S. in Elementary Education an associate
professor in the Department of Biological Sciences at Plattsburgh
State University in Plattsburgh, New York.
S C I E N C E
sampler
Procedure
1. Add 12 to15 drops of red food coloring to 100 mL of
tap water in a flask or beaker. Swirl to mix, and label
“Solution A” with tape and marker. This will be your
stock solution for all red solutions.
2. Make 200 mL of a 1:10 dilution from solution A by adding one mixing one part of Solution A with 9 parts of
tap water in a separate beaker. Label this “Solution B.”
3. Make 100 mL of a 1:20 dilution from solution B. Label
this “Solution C.” List the steps you took to make this
solution.
4. Add 12 to 15 drops of blue food coloring to 100 mL of
tap water in a flask or beaker. Swirl to mix, and label
Answer key for solution calculations
Solution B 200 mL/10 (df) = 20 mL of Solution A
added to 180 mL (9 parts x 20 mL) tap water.
Solution C 100 mL/20 (df) = 5 mL of Solution B
added to 95 mL (19 parts x 5 mL) tap water.
Solution 2 100 mL/50 (df) = 2 mL of Solution 1
added to 98 mL (49 parts x 2 mL) tap water.
Solution 3 100 mL/2(df) = 50 mL of Solution 2
added to 50 mL (1 part x 50 mL) of tap water.
The different concentrations of red food
coloring in solution
PHOT0S BY JOHN WAYNE JOHNSTON
FIGURE 1
“Solution 1” with tape and marker. This will be your
stock solution for all blue solutions.
5. Make 100 mL of a 1:50 dilution from solution 1. Label
this “Solution 2.” List the steps you took to make this
solution.
6. Make a 100 mL of 1:2 dilution from solution 2, label
this “Solution 3.” List the steps you took to make this
solution.
7. Have the students line their lettered solutions next
to each other (Figure 1) and their numbered solutions
next to each other (Figure 2).
FIGURE 2
FIGURE 3
Measuring out
20 mL from Solution A
in order to make
Solution B
The different concentrations of blue food
coloring in solution
JOHN WAYNE JOHNSTON
March 2 0 0 6
science scope
43
S C I E N C E
sampler
Girls, robots, and
science education
The word robot can have various meanings to different people.
To some, a robot is a human-like machine that thinks and acts
independently. To others, a robot is any device that does work
humans would rather not or cannot do. For our broad purposes, a
robot is an autonomous device that has sensors and uses feedback
to interact and/or behave in its environment. It follows that robotics is the study of robots and how they work. (See Resources
for more definitions.)
Why teach robotics? This question comes to mind as science
educators read about the successful use of robots in classrooms
around the world. There is much anecdotal evidence found in
professional magazines and journals to support the notion that the
robotic experience offers students opportunities for higher-order
thinking, creative expression, and discovery learning (Mauch
2001, Bruder 1993, and Resnick 1990). Students working in
small groups can build, decorate and then program robots like
the LEGO Mindstorm (see Resources). As part of a new, multidisciplinary unit students can dabble in neuroscience as they reconfigure the brain of Edvotek’s new SlugBug the Neuromorphic
robot (see Resources). These types of learning experiences have
been shown to motivate learners regardless of location, socioeconomic status, or gender (Wagner 1999 and Frontiers 1998).
Diversity in most environments is critical to success. The dominance of males in the fields of engineering and computer science
has created a homogenous population of technology scientists.
Statistical research funded by the National Science Foundation
(NSF) shows that the percentage of women getting a bachelors
degree in engineering has increase from .4% in 1966 to 20.1% in
2001. This increasing number of female engineers is encouraging, however, well under a desired 50%. While mathematics and
computer science degrees for young women have increased in
recent years, female representation in the field remains a low 31%.
These facts have lead the NSF and the Department of Education
(DoE) to offer funding for innovations in science education. These
innovations should be targeted at under-represented populations
and it is hoped that they will attract more young women and
minority students into the technological sciences.
Science instruction with the implementation of robotics
could provide girls with the needed impetus. Robots offer
the opportunity for creative expression, problem solving, and
constructionist learning. The challenging skills of mathematics and computer programming are deeply embedded in the
novelty and kinesthetic nature of the robot. The introduction
to robotics at a young age could open doors and pique the
imaginations of adolescent girls.
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March 2 0 0 6
The study
Descriptive research was conducted to assess middle school
student attitudes towards robots, technology, and science (Rogers 2003). Gender differences were studied. The subjects were
53 sixth-grade students and 74 eighth-grade students from
Charleston, Illinois. Observational checklists were completed to
examine student behavior in the science classroom. A questionnaire consisting of 20 items was administered to the male and
female students to determine their attitudes towards robotics
and technology and to explore if gender differences existed in
their responses. Interviews were conducted with eight randomly
selected female middle school students to obtain more in-depth
information on their perceptions and attitudes towards robots,
technology, and science. Results showed that middle school
students exhibited positive attitudes towards robotics, careers in
robotics, science, and technology. It was also revealed that middle
school girls have a significantly more positive attitude towards
careers in robotics than their male counter parts.
Standards abound
Robotics lends itself naturally to the National Education Technology Standards (NETS). These standards
J. Jill Rogers (jill@iguana-robotics.com) is Director of Educational
Robotics at Iguana Robotics in Urbana/Champaign, Illinois. Marylin
Lisowski (cfmfl@eiu.edu) is a professor of science and environmental
education at Eastern Illinois University in Charleston, Illinois. Amy A.
Rogers (arogers@desu.edu) is an assistant professor in the department
of psychology at Delaware State University in Dover, Delaware.
S C I E N C E
sampler
are offered to teachers as guidelines for lesson plans (see
Resources). Of the six broad standards listed, a roboticthemed unit naturally addresses five standards. The ethical
and problem-solving standards listed below are addressed
by robotics in a unique way:
1. Social, ethical, and human issues
• Students understand the ethical, cultural, and societal
issues related to technology.
• Students practice responsible use of technology systems,
information, and software.
• Students develop positive attitudes toward technology
uses that support lifelong learning, collaboration, personal
pursuits, and productivity.
2. Technology problem-solving and decision-making tools
• Students use technology resources for solving problems
and making informed decisions.
• Students employ technology in the development of strategies for solving problems in the real world.
Easy robot activities
Many robotics-related activities can be presented in the
classroom, even without an expensive robotics kit. Old,
broken robot toys like “Furby” by Hasbro or “Techno the
dog” can be found in garage sales or at the bottom of your
toy box. Collect a few and stage a robot dissection—complete with rubber gloves and sanitary masks. Once the
robot is open, locate for your students basic robot internal organs: sensors, servos, and Central Processing Unit
(CPU). This activity opens the “black box” of technology
and invites students to consider the engineering and science behind the toy.
For an easy to set-up lab activity, ask students to bring
in working robot toys. “Robosapien,” a popular robot toy
made by WowWee Robotics, has many sensors and features, and the new Furbys are also quite complex for a toy.
Set up different robots around the room and have students
work in small groups to conduct informal experiments.
The objective is to determine which types of sensors are
present in each robot and where they are located. As
they work, have students record their methods of sensor
testing (clapping hands, shaking the robot, and so on).
At the end of the lab activity, groups discuss their findings and compare their results to the information found
in the robot’s user manual. This activity could lead the
class to a discussion of different types of sensors, as well
as experimental methods.
More information on the history of robotics and other
classroom materials can be found in “Robo Info: Fun Facts
and Activities.” This book was written for classroom use with
funding from the National Science Foundation and can be
downloaded for free (see Resources). The book includes quick
demonstrations of the feedback principal, creative robot art,
and ways to think about programming, as well as a complete
glossary of robot terms.
Acknowledgments
Special thanks to Patti Murphy and Debra Landsaw from Jefferson
Elementary School, Charleston, Illinois, Tim McCollum from
Charleston Junior High, Charleston, Illinois, for opening up
their classrooms for this research, and to Geoff Freymuth, Edison
Middle School in Champaign, Illinois, for his participation in the
continuation of this work.
References
Bruder, I. 1993. Redefining science: Technology and the new science
literacy. Electronic Learning 12 (6): 20–24.
Frontiers. 1998. High-Tech toys as teaching tools. The Technology
Teacher 58 (2): 33–36.
Mauch, E. 2001. Using technology innovations to improve the
problem-solving skills of middle school students: Educators’
experiences with the Lego Mindstorms robotic invention system.
The Clearing House 74 (4): 211–213.
Resnick, M. 1990. MultiLogo: A study of children and concurrent
programming. Interactive Learning Environments 1 (3): 153–170.
Rogers, J.J. 2003. Middle school student attitudes towards robotics,
science and technology. Master’s thesis. Eastern Illinois University.
Wagner, S.P. 1998. Robotics and children: Science achievement
and problem solving. Journal of Computing in Childhood Education
9 (2): 149–192.
Resources
Inexpensive kits—http://electronickits.com/robot/robot.htm, www.
hobbytron.net/main.html
LEGO Mindstorms for Schools—www.lego.com/eng/education/
mindstorms
NETS learning standards—http://cnets.iste.org
Robotics lesson plans—http://www.ircs.upenn.edu/pennlincs/robotics.htm
SlugBug the Neuromorphic robot kit and “Robo Info: Fun Facts
and Activities” free download for classroom use—www.
slugbugrobot.com
What is a robot?—http://www.virtuar.com/click/2005/robonexus
Additional information
American Association of University Women Educational
Foundation. 2002. Tech savvy: Educating girls in the new computer
age. Washington, DC: AAUW.
Buck, G. 2002. Teaching discourses: Science teachers’ responses to
the voices of adolescent girls. Learning Environments Research 5
(1): 29–50.
Papert, S. 1980. Mindstorms: Children, computers and powerful ideas.
New York, NY: Basic Books.
March 2 0 0 6
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S C I E N C E
sampler
Phasing in lunar
observations
We describe an interdisciplinary Moon unit that was recently
enacted in seventh grade science, mathematics, and English
classrooms with three experienced teachers and 186 energetic
students. Within the unit we incorporate aspects of the National
Science Education Standards (NRC, 1996), the National
Council of Teachers of Mathematics Principles and Standards
(NCTM, 2000), and the National Council of Teachers of English
Standards (NCTE, 1996). This interdisciplinary unit lasts six
to seven weeks where students explore the phases of the Moon
through science, mathematics, and language arts. In order to
gauge students’ prior knowledge regarding the Moon and its
phases, we administer the Lunar Phases Concept Inventory or
LPCI (Lindell 2000). Questions on the inventory include the
time of a lunar cycle, the direction of the Moon’s orbit, and
the cause of the Moon’s phases. Figure 1 illustrates an example
question from the LPCI. For a complete copy of the inventory,
contact Dr. Rebecca Lindell at rlindel@siue.edu. We also use this
inventory at the end of the unit to assess student learning.
Lunar Phases Concept
Inventory sample question
FIGURE 1
19. If you could look down on the Eath/Moon/Sun system
from a point in space located above the Earth’s North Pole,
you would observe that the Moon orbits around the Earth.
At one Point in time it is in position A, as shown below. At
some later time, the moon is now in position B.
Orbit of the Moon
B
A
E
S
How much time passed between these two observations?
a.
b.
c.
d.
1 hour
3 hours
6 hours
1/2 day
e.
f.
g.
h.
1 day
1 week
2 weeks
3 weeks
i. 1 month
j. More than 1
month
Phase one
We begin this unit by having students observe the Moon over
a five-week time period. They are asked to make sense of their
Moon observations and are required to keep a daily Moon
journal. In this journal, students are given an invitation to write
“whatever they wish and think is relevant” with at least two
sentences per entry. Students can conduct their viewing sessions
on their own, or invite family and even pets to accompany
them. Students are encouraged to use descriptive language when
making their observations, and to supplement their entries with
poetry, sketches, and other artistic endeavors inspired by their
nocturnal viewings. This approach generates a mix of creative
and scientific entries. On the same page you are apt to find the
Moon described both as a “watermelon in the sky” and a “waxing
gibbous.” Meteorological conditions will often be layered below
prose, as evidenced in this student verse.
The full Moon glows with its soothing light
Not a single star glimmers on this cold Thursday night.
As I breathe, a cloud forms in front of my face, and I hear
The Wind blow, at a quick, steady pace.
Phase two
In English class students read multicultural, mythological tales
surrounding the Moon and natural phenomena. Students also
take turns each day reading a tale to their class from Joseph
46
science scope
March 2 0 0 6
Bruchac and Jonathan London’s, Thirteen Moons on Turtles Back:
A Native American Year of Moons. In addition, students compile
lists of nature-oriented figurative language. These lists contain
entries from their Moon journals, for example “the peaceful Moon
calms the inner soul,” and a portrayal of the Moon as a “lantern
in the sky.” This language broadens students’ descriptive powers,
and is put to practical use in their next assignment, The Moon
Phases Poetry and Legends Scrapbook.
Over a period of approximately two weeks, students create
their scrapbooks (using materials such as, construction paper,
yarn, markers, and glitter). Within the scrapbooks, students assemble their own images and depictions of the Moon. They can
be original illustrations and prose; and/or imagery and descriptions taken from magazines, websites, and books. The language
arts teacher provides additional instruction on painting, drawing,
and collage techniques to help students express and organize
their collections. Prior to these art lessons, we present students
with an assortment of art prints of lunar images for the purpose
of inspiration and to show the many different ways that people
Jennifer Wilhelm (jennifer.wilhelm@ttu.edu) is an assistant professor of
mathematics and science education, Sally McMillan (sally.tyler@ttu.edu)
is an assistant professor of language arts, and Kendra Walters (kendra.
l.walters@ttu.edu) is a doctoral student in mathematics and science education in the in the College of Education at Texas Tech University in Lubbock
Texas. Emma Lovering (ehintze@lubbockisd.org) is a seventh-grade
science teacher at Ed Irons Junior High School in Lubbock, Texas.
S C I E N C E
sampler
FIGURE 2
Examples of artwork used in
The Moon Phases Poetry and
Legends Scrapbook and poems
inspired by observations.
Blue Moon
Seems like on some nights when you are scared of the
world and alone
You cover up with a blue blanket to block out
the crime and evil events
Just like a little girl does when she hears thunder
Some nights I feel like climbing stairs up to you and
doing the same.
The Moon and I
Between you and me Moon
I like you the best
As your light enhances the evenings
I enjoy a peaceful rest.
Without your bold appearance
The night sky would be so dark
Of all the other twinklings
You seem to make the mark.
So please keep shining upon me Moon
As I go through the night
And I will gaze forever
Upon your wondrous light.
have visualized the Moon. Examples of prose and an illustration
of students’ work are shown in Figure 2.
Phase three
After completing the five weeks of lunar observations, students
model the phases of the Moon using styrofoam balls to represent
the Earth and Moon, and an overhead projector to represent
the Sun (see Figure 3). Students refer to their journal observa-
tions to help them
correctly position the
Moon, Sun, and Earth
to create, for example, a waxing crescent
Moon phase. The geometric configuration
that students finally
construct (Figure 4)
demonstrates that the
Students create the correct geometric Earth’s shadow plays
configurations for various Moon’s phases no role in creating the
using styrofoam balls (representing the observable crescent
Earth and the Moon), and an overhead shape. The shadow
misconception is a
projector (representing the Sun).
commonly held belief
of middle-school students. As an extension, students try to determine the geometric configuration needed for the Earth to cast
a shadow on the Moon (which would be a lunar eclipse) where
they correctly arrive at the situation shown in Figure 5. Through
the styrofoam modeling of the Moon’s phases, students also come
to realize that this is the particular geometrical configuration
(shown in Figure 5) necessary for the full Moon phase. They
come to understand that the Moon appears full since most of
the time it is either above or below the Earth/Sun plane.
Final phase
At the conclusion of the Moon unit, students are given a post
LPCI in order to measure their post unit understanding. We have
implemented this unit with classes for the past three years. In using
the LPCI as an instrument to assess students’ learning of the Moon
and its phases, we have observed significant gains from pre to post
on every occasion. For example, the students showcased in this
piece also displayed a significant increase in lunar understanding.
The t-test for paired data at the α = .05 level, showed a significant
difference in the means, t(104) = -7.18, p = 1.082 x 10-10.
References
Lindell, R. Lunar 2002. Phases Concept Inventory. Southern Illinois
University.
National Research Council. 1996. National Science Education
Standards. Washington, DC: National Academy Press.
National Council of Teachers of English. 1996. Standards for the
English language arts. Urbana, IL: Author.
National Council of Teachers of Mathematics. 2000. Principles and
standards for school mathematics. Reston, VA: Author.
Texas Essential Knowledge and Skills. www.tea.state.tx.us/teks/
index.html.
Bruchac, J., and London, J. 1997. Thirteen Moons on Turtles Back: A
Native American Year of Moons. Putnam Publishing Group.
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