Introducing students to the
world of digital microscopy
By MacGregor Kniseley and Karen Capraro
54
Science and Children
Photographs by MacGregor Kniseley
Small
Wonders
L
Close
Encounters
ooking at small objects through a digital microscope
is like traveling through a foreign country for the first
time. The experience is new, engaging, and exciting! A
handheld digital microscope is an essential tool in a 21stcentury teacher’s toolkit and the perfect tool to engage
elementary students across the grade levels in the 21stcentury curriculum. This article, which provides elementary teachers a starting point for using handheld digital
microscopes, describes how a second-grade teacher introduces students to microscopes as scientific tools. Students
observe, capture, and interpret still, video, and time-lapse
images of structures of mealworms with handheld digital
microscopes. By using digital microscopes, students view
firsthand evidence of small wonders in science, solve problems, ignite creative thinking, and create digital artwork.
By planning lessons that include handheld digital microscopes, teachers can align their instruction with the
Next Generation Science Standards. Students can learn science and engineering practices (e.g., developing and using models and planning and carrying out investigations),
crosscutting concepts e.g., structure and function), and
multiple disciplinary core ideas. In this case, the disciplinary core idea was 2-LS4-1, in which students make observations of animals to compare diversity (Achieve Inc.
2013; see Internet Resources).
Comparing Insects and
Microscopes
For the past eight years, I have used Lawrence Hall of Science’s Full Option Science System (FOSS) (2000) for teaching
hands-on science in my second-grade classroom. During the
fall, we use the FOSS Insects science module to investigate
and compare structures, behaviors, and metamorphosis of
several insects, including darkling beetles, American painted
lady butterflies, and crickets. We begin with the darkling
beetle and go on to compare the structures of all insects with
one another to better understand their diversity. The kit includes live insects, supplies for habitats, plastic hand lenses
for observing, and forms for recording observable changes
in the structures of the darkling beetle over time. For information about care and maintenance of mealworms (darkling
beetles), visit FOSSWEB (see Internet Resources).
To enhance our observations further, we used digital and
compound microscopes in addition to the provided plastic
hand lenses during three one-hour lessons. Our school had
recently purchased three digital microscopes (see “Purchasing a Digital Microscope,” p. 56). Finding compound microscopes was a little bit more challenging! After rummaging around our school, I located three dusty, old compound
microscopes. After cleaning them off, I set up three stations
in the room, one for conducting observations using the FOSS
hand lenses, one using the compound microscopes, and one
using digital microscopes. I created three groups and rotated
the groups of students through the three stations.
During whole-class teaching I increase active participation by having students take turns using the digital microscope at the presentation area. Meanwhile, students at
their desks observe the same objects using less expensive,
lower magnification plastic hand lenses. Alternatively,
students can draw, label, and describe a projected digital
microscope image.
Introducing the Digital
Microscope
F i g ure 1.
Digital microscope images of
mealworm larva structures.
The first time I used digital microscopes with students, I
shared ground rules for safe and responsible use:
F igu re 2.
Class Chart: Property, Structure, and
Function.
After students observed and captured images
of mealworm larvae with handheld digital
microscopes, their teacher recorded students’
thinking about properties, structures, and functions
on a class chart.
Photograph by MacGregor Kniseley
Photograph by MacGregor Kniseley
Head and antennae structures of mealworm
larva
Head and thorax structures of a mealworm larva
September 2013
55
1. Respect the equipment.
Purchasing a Digital Microscope
2. Hold the digital camera carefully.
Purchasing a digital microscope is like buying a car.
There are many companies who sell similar products.
Products are sold with a wide range of options.
There are differences in the products. Pricing
varies according to features and kit packages.
Digital microscopes should be durable and include
magnification ranging from 0x to 200x; USB cable;
controlled lighting; a flexible stand for hands-free
viewing and recording; digital imaging software for
capturing still, video, and time-lapse; and a snapshot
button on the base. The digital microscope’s image
should be high resolution (1280 x 1024) and display
well using classroom projection systems.
“Test drive” your digital microscope! Most vendors
provide teachers free, short-term loan agreements. You
can use the digital microscope in the classroom for
2–4 weeks before returning or purchasing.
When comparing different brands of digital
microscopes, consider these dimensions:
3. Keep the lens dry. If the lens comes in contact with
any wet or sticky substance, clean and dry it immediately.
4. Work with the digital microscope on dry tables.
After demonstrating some of the features of the handheld digital microscopes, I taught students to observe and
capture still images. (Later, they learned to use other features—capturing video and time-lapse images, measuring, and using the side-by-side feature.)
We have a classroom nature center, and throughout
the year I encourage students to add living and nonliving natural materials to the center. Students observed and
drew objects using the naked eye first, next with a 6–10×
plastic magnifier, and then with a higher power digital
microscope. They maintained a scientist notebook by
writing and drawing what they observed and discussing
their observations with each other. I changed the objects
in the center periodically to maintain interest. The center
included field guides (see Internet Resources) to insects,
wildflowers, pond life, and other nature topics to encourage further research about the living things—beginning
with observing and capturing still images.
• cost
• product warranty and replacement parts
• compatibility with computer operating systems
• type of lens and magnification
• higher or lower resolution images
A Closer Look
56
Science and Children
• adjustable or on/off lighting
• features of digital imaging software
• battery operated or USB-powered
• connectivity—USB cable or wireless
• ease-of-use for teachers and students
• training and technical support
• kits and other instructional materials
Photo courtesy of EUGene st. Pierre
I introduced students to microscopes as scientific tools
that enhance observation by reading Millicent Selsam
and Arnold Lobel’s Greg’s Microscope (1963) to engage
students and help them understand that microscopes are
used to observe “tiny things,” things that are unobservable with the naked eye. Then, I paired students to use the
digital microscopes.
“Wow! Cool!” exclaimed my students as I handed each
of them a darkling beetle larva and we began our study of
comparing insects. They eagerly began carefully investigating the wormlike creatures in an effort to answer our question: Is a mealworm an insect?
They observed mealworm larvae closely, described the
properties, and captured still images of their observations
(see Figure 1, p. 55).
The following lesson, I projected digital microscopic images of mealworm larva on the whiteboard and we charted
the structures (head, thorax, abdomen, legs, claws, antennae, mouth, spine) properties, and functions (see Figure 2,
p. 55). Students described the properties of their observed
structures and suggested similes. Then, students observed
mealworm larvae a second time with their naked eye and
a digital microscope. Students visually represented their
Small Wonders Close Encounters
F i g ure 3 .
Recording form for communicating
scientific thinking.
Students acquired and used more vocabulary and
figurative language and labeled structures more
accurately after using digital microscopes.
Conclusion
I have always been satisfied using the FOSS Insects kit, but
this year was different. By teaching these lessons using digital microscopes, I noticed considerable improvement in my
students’ ability to produce accurate scientific drawings.
They more easily labeled their mealworm larva structures
while expanding their scientific vocabulary and developing
an understanding of the differences between these living organisms. Additionally, all of my students were confident in
their ability to identify the body parts of the mealworm and
relate structures and functions. My students were able to determine that mealworms were indeed insects!
The time I added to the lessons for investigating microscopes as scientific tools was time well spent. My students not
only were more able to understand and identify the structures
of their mealworms, but also more able to identify properties
and use descriptive language to communicate their understandings. All my students, regardless of ability, were highly
engaged in these lessons. I heard students saying, “I want to
get a microscope!” My students felt empowered as scientists
while using the tools that scientists use. n
F igu re 4.
Card stock slides and digital image
of salt.
Photographs by MacGregor Kniseley
thinking by drawing and labeling the structures, listing
properties, and writing similes (see Figure 3).
I began the next lesson by discussing the various types
of microscopes scientists use in their work. I returned to
Greg’s Microscope and asked students to compare and contrast the handheld digital microscopes with Greg’s compound microscope. We made card stock slides of “tiny
things” observed by Greg such as flour, salt, sugar, and
pepper (see Figure 4). Students observed the slides using
both types of microscopes. They independently completed Venn diagrams to document similarities and differences
of the two different microscopes (see Figure 5, p. 58). We
concluded the lesson by completing a Venn diagram as a
class while discussing similarities and differences. Then,
we viewed micro-photographs and read about a professional microscopist in Stephen Kramer and Dennis Kunkel’s Hidden Worlds (2001).
September 2013
57
Small Wonders Close Encounters
Differentiation Strategies
Early Childhood Education Students
Students of all ages can use digital microscopes. However,
early childhood students need to learn to focus objects
and understand “part and whole” before using the digital
microscope effectively. Teachers can easily teach “infocus” and “out-of-focus.” First, teachers demonstrate the
attributes of “in-focus” (e.g., clear, sharp) by projecting
an image and adjusting the digital projector in and out of
focus until students recognize the conditions for “in focus”
and “out-of-focus.” After students have an understanding,
teachers and students can do the same while using a
digital microscope. Students can explain the meaning of “in
focus” and “out-of-focus.”
Next, to teach the concept “part and whole,” students
can be asked to hold up an empty paper towel tube up to the
bones around their eyes and look through the tube at their arm
or at another student across the room. Students can describe
the part of the whole they observe. Then, students can play the
mystery picture challenge. Capture images of a part of a whole
(e.g., fabric from a shirt, end of index finger, a shiny penny, the
tip of a pencil) and project the images separately. Students can
guess the “whole” by viewing the “part.”
Special Education Students
Special education students can also use digital microscopes
with little assistance. While using the microscope during
a hands-on science lesson, students can apply relevant
literacy skills—observing, predicting, comparing, inferring,
and communicating. Students rely less on reading and
written communication and more on drawing and speaking.
If needed, additional accommodations can be made
by assigning a special education student to a general
education student until independent use is achieved.
ELL Students
Teachers can help English language learners at different
levels of proficiency acquire and use vocabulary when using
digital microscopes. Here are several instructional strategies:
1. When introducing the digital microscope, label the parts
(base, lens, USB cable, computer) on the equipment.
2. Use a clear, pictorial step-by-step guide for teaching
how to operate a digital microscope.
3. Create a pictorial science word wall. Post new science
vocabulary in columns according to the level of
organization.
4. Use graphic organizers such as Venn diagrams and
concept maps.
58
Science and Children
F igu re 5.
Student’s Venn Diagram.
Grade 2 students compared a digital microscope
and a traditional compound microscope and
recorded their thinking in a Venn diagram.
MacGregor Kniseley ([email protected]) is a professor of elementary education at Rhode Island College in
Providence, Rhode Island. Karen Capraro (kcapraro@
ric.edu) is an associate professor at Rhode Island College and teaches second grade at Rhode Island College’s
Laboratory School, Henry Barnard.
References
Achieve Inc. 2013. Next generation science standards. www.
nextgenscience.org/next-generation-science-standards.
Kramer, S., and D. Kunkel. 2001. Hidden worlds: Looking
through a scientist’s microscope. Boston: Houghton Mifflin.
Lawrence Hall of Science. 2000. Insects. Full Option Science
System. Nashua, NH: Delta Education.
Selsam, M., and A. Lobel. 1963. Greg’s microscope. New York:
HarperCollins.
Internet Resources
FOSSWEB
http://lhsfoss.org/fossweb/teachers/materials/plantanimal/
tenebriobeetles.html
Golden Guides
http://us.macmillan.com/series/
AGoldenGuidefromStMartinsPress
NGSS Table: 2-LS4 Biological Evolution: Unity and Diversity
www.nextgenscience.org/2ls4-biological-evolution-unitydiversity
NSTA Connection
For the lesson rubric and more digital microscope
activities, visit www.nsta.org/SC1309.