Small Worlds Close Encounters
Chapter 6 - Fun Digital Microscope Activities
Explore the different features of the handheld digital microscope. Begin your
explorations by capturing still images of flat objects. As your learn to focus and adjust
the light for clear, sharp images, capture solid, irregular-shaped objects and live
organisms. Next, try your hand measuring small objects, comparing images side-by-side,
and capturing video and time-lapse images.
The Penny
Before observing a penny, clean it with some vinegar so it appears bright and shiny.
Before observing, students can draw an enlarged view of the heads/tails sides on an 8
1/2 x 11 inch sheet of paper and include as many details as possible. Next, they can use
the digital microscope to observe and capture images of the penny. Notice Abraham
Lincoln sitting inside the Lincoln Memorial. And, observe the initials FG at the lower right
side of the Memorial. The initials represent Frank Gasparro, the most famous artist you
never heard of! Over 100 billion copies of Gasparro’s Lincoln Memorial have been
reproduced! Finally, students can return to their drawings and add missing details.
Five-Dollar Bill
Observe and count the names of states on the Lincoln Memorial. Which states are
missing from the bill? Notice the different ink colors such as the yellow numbers. Anticounterfeit experts added to the recent $5 bill more detailed watermarks, microprinting, a security thread containing over 650,000 tiny glass domes, and light purple ink
that fades to gray at the edges of the bill. If available, compare an older $5 bill with the
recent bill.
CSI - Fingerprinting
Use the digital microscope to observe tiny ridges and valleys on the tips of your fingers.
Notice the whorl, loop, and arch pattern. Also, check for shiny droplets coming from
sweat glands in your finger. Next, capture and print two copies of everyone’s fingerprint
from the same finger, same hand. Divide the class into small groups. Have one group
member (detective) leave the group temporarily while one of the remaining group
members (criminal) selects a group member’s fingerprint. The detective returns to
“scene of the crime” and compares all group members’ fingerprint images to the
criminal’s fingerprint. The detective identifies the criminal. Crime solved!
Observing Objects Around the School
Students don’t need to go far to find interesting materials to observe and compare.
Here are some different materials found on the person, classroom, cafeteria,
playground and teacher or principal’s desk:
• Person: skin, fingernails, hair, pocket lint, shirt fabric, shoe fabric
• Classroom: chalk, pencil and pen points, pencil shavings, eraser crumbs, paper clips,
paper, dust
• Cafeteria: small pieces of bread, fruit, chips, salad items
• Playground: pavement, sides of buildings, rocks, leaves, soil, insects, dandelions,
grass
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Small Worlds Close Encounters
•
Teacher or Principal’s Desk: paper clips, pens, staples, and “Catch You Being Good”
reward slips
Microscopic Scavenger Hunt - Twenty Questions
Conduct a Microscopic Scavenger Hunt. Capture still images of objects from your
school playground and insert the images into a Microsoft Word document. Play the
game Twenty Questions. Display a still image of a small object taken with the digital
microscope inside or outside the classroom. If needed, offer hints about the object.
Classroom Nature Center
Set up a classroom nature center and encourage students to add living and nonliving
natural materials to the center. Students can observe objects using the naked eye first
and then again with the digital microscope. They can maintain a Nature Journal by
drawing and writing what they observe and discussing their observations with each
other. Change the objects in the center periodically to maintain interest. In the center,
include relevant children’s nonfiction or Golden Guides to insects, plants, pond life, and
other nature topics to encourage further research about the natural materials.
Microscopic Explorations Learning Center
Set up a GEMS Microscopic Explorations learning center in the classroom. Rotate small
groups of students through the center. Create small group cooperative roles (e.g.,
Getter, Reader, Starter, Checker). Students can rotate roles with each new activity. See
GEMS Microscopic Explorations section in this book for brief descriptions of ten center
activities.
The Private Eye Approach
The Private Eye is an instructional strategy to observe common objects with a magnifier,
drawing while observing with a magnifier, and thinking by analogy. The magnifier
enhances students’ focus on details and patterns. While observing, students think by
analogy. “What does this remind me of?” Students observe with meaning, connect
form with function, solve problems, and draw inferences. See Gallery of Images of
Writing and Drawing at http://www.the-private-eye.com/html/galleries/galmenu.html
See Kerry Ruef’s The Private Eye in Teacher Resources.
Microscopic World Bookmark
Use the Table tool in Microsoft PowerPoint. Insert images captured by the digital
microscope in a one-row table in the document.
Microscopic
World
Bookmark
50 x images of a
newspaper photo
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Small Worlds Close Encounters
Print copies on cover stock and distribute the bookmarks at a family science night or
open house.
Secret Message
Use the Object Palette tool in Microsoft Word to make a 3-inch black dot. Insert a text
box and type a secret message inside the black dot. Type the secret message in white
font on the dot and then reduce the font size (4 pt) so the text is too small to read with
the naked eye. Print it out using a high quality printer. Read the secret message using
50x magnification.
What did Mars say to Saturn?
Observe black dot with 50x lens and find
the secret message.
Secret Message
Still image (50x) from Digital Microscope
Shapes and Colors
Observe shapes and colors in natural materials. Here are some shapes and materials to
observe include:
• Square – salt crystals, iron pyrite, fabrics
• Rectangle – fabrics
• Triangle – tips of fern fronds, flower (trillium), fish scales, spider webs
• Circle – drops of water, spores on fern frond, radish seeds, mushroom cap, acorn
shell, whorl patterns on fingerprints
• Heart – red bud, aspen
Patterns in Nature
Observe different materials and discover form and symmetry in nature.
To introduce the concept, view a six-minute video by Amy Lamb at
http://www.amylamb.com/films.html
The video of her 2007 US Botanical Garden exhibition illustrates various patterns in
nature. Lamb explains how beauty can be found through form (e.g., branches, layers,
spirals) and symmetry (e.g., radial and bilateral) in flowers and other natural materials.
Here are examples of patterns and materials:
Form:
Branches - feathers, branches on twig
Layers - buds, fish scales, snakeskin
Spirals - snail shell, fiddlehead fern
Symmetry:
Radial - snowflake, starfish, sunflower
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Small Worlds Close Encounters
Bilateral - insects
Larger-Than-Life Fingerprints; Fingerprint Quilt
Have students make colorful, larger-than-life drawings of their fingerprint on a piece of 8
1/2 x 11 inch paper. View examples of student drawings in the Fingerprint Gallery at
http://www.the-private-eye.com/html/galleries/fp2html/gal2.html
Arrange your students’ fingerprint drawings in a Fingerprint Quilt. View an example of a
Fingerprint Quilt in a poster at
http://www.the-private-eye.com/html/aboutTPE/WhatsNew.html
Sand at the Beach
Collect sand from different parts of the beach or from different beaches around the
world. Do the sand particles look the same? Go to the International Sand Collectors
Society web site at http://www.sandcollectors.org. View sand from around the world in
the Gallery. Or, view sand organized by continents in The Virtual Sandbox at
http://www.ajaster.com/Sandbox/index.html
Yuck! Decaying Fruits!
Observe and capture images of bacteria and fungi growing on over-ripened
strawberries, lemon and other fruits. Take a bite of an apple. Capture an image of this
section. Observe and capture an image after the oxidation reaction. Continue to
observe and capture images of the apple and growth of bacteria and fungi. Compare
the images over time. You can also use the time-lapse feature for this activity.
Germinating Seeds
Purchase about 5-10 different seeds (e.g., corn, lima beans, alfalfa, mung beans,
sunflowers, pumpkin seeds). Have students observe dry seeds with the digital
microscope. To germinate the seeds, moisten a paper towel. Place seeds on the wet
paper towel in a zipper sandwich bag or clear plastic cup. Keep the towel moist. After
several days, observe the germinating seeds under the digital microscope. Capture
images of seeds at different stages of growth (e.g., the seed coat breaking, emerging
roots, small ‘hairs’ at the end of the roots). You can also use the time-lapse feature for
this activity.
Drawing Scientifically
Teach students to observe carefully and draw the finer details of an object – to draw
like a scientist. Careful drawing while closely observing improves observation skills.
Drawing helps students focus on the details of the material. Without drawing instruction,
some younger students draw cartoonish figures that feature obvious properties of color
and shape. Explain the difference between a cartoon and scientific drawing. For
example, make a cartoon drawing of an insect or spider with a circle and a dot in the
middle representing the eye. Then, draw the eye more scientifically. Have them draw
details of an insect or spider eye scientifically.
Improving Observation and Visual Memory
First, challenge students to observe an object with a digital microscope for a period of
time and identify and remember five features to draw away from the microscope. Next,
students return to their desks, draw the object, and label five features they can
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remember. Then, students return to observe the object a second time and determine if
the drawing is accurate.
Micro Drawings
Print a digital image of an object. Draw a grid over a photo. Draw a similar size grid on
blank paper. Notice on the grid the location of each part of the object. Draw the part
in the matching areas of the blank grid. Label the parts. Write a title and date. See the
technique for drawing using a grid suggested on p.17 in The Usborne Complete Book of
the Microscope book listed in Teacher Resources section.
Science Investigations
Use a digital microscope to collect evidence during authentic science investigations.
Here is an example of an investigation conducted by third graders:
• Focus Question: How clean are my hands during the day?
• Prediction: When I wash my hands, I’ll observe less dirt.
• Procedure: 1. Use a digital microscope to capture three images of the same area of
your right index finger three times during the school day - in the morning, after
washing hands before lunch, and after lunch recess. 2. Print images.
• Data-Observations: Observe, label and describe the properties.
• Claims and Evidence: Analyze and compare the images. “I know this to be
true…Here is the evidence.”
• Conclusions: Formulate conclusions. “I used to think (predictions) … Now I think….I
learned…”
• Next Steps-New Questions: Propose questions to investigate and actions to take.
View Prepared Microscope Slides
View prepared glass slides that are mounted and individually labeled - ready for
observation under the digital microscope. You can purchase eight “My First Lab” minisets from C&A Scientific. Go to
http://www.myfirstlabmicroscopes.com/mini_slide_sets.html.
Each set includes five prepared slides and interesting facts about the specimens.
• Blood & Guts – mammal brain tissue, human heart, human blood, human
stomach, small mammal kidney
• Extraordinary Ordinary - the letter “e”, straight and curly human hair, cork, fibers
and tobacco, 3 colored dyed fibers
• Incredible Edible Plants – onion roots, corn stem, tomato leaf, carrot root, rice
leaf
• Wicked Wings - bee, butterfly, fruit fly, housefly, mosquito wings
• Flower Power – sunflower stem, buttercup stem, lily leaf, lotus root, rose petal
• Lily Pad Leap - Frog intestine, kidney, liver, skin, lung
• Fun Guys – Bread mold, penicillin, lichens, mushroom, yeast
• Creepy crawlies - Earthworm, planaria, ant, mosquito legs, honeybee mouth
Comparing Images Side-by-Side
Use the side-by-side feature to observe and compare the images of two small objects.
Place some sugar and salt on a piece of black construction paper. Separate the salt
and sugar and observe the crystals. Capture images and project them side-by-side. Ask
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students how the crystals are similar and different. Students can organize their thinking in
a Venn diagram or a same-different chart.
Measuring
Use the measuring feature to compute distance, surface area, and angles of small
objects. Measure and compare the width of salt and sugar crystals or different strings.
Measure the surface area of two different coins.
Capturing Video and Time Lapse Images
Capturing and interpreting video and time-lapse images bring students closer to
microscopic events in nature. For instance, students can capture images of different
seeds germinating, crystals forming from saturated saltwater, or a phase change of
melting ice cubes. After recording images, students can deepen their understanding by
viewing and interpreting the video images.
To get started, practice capturing time-lapse and video images of an analog clock
second hand on a wristwatch or smartphone. Then, try some of these time-lapse and
video life, earth, and physical science activities. After building a collection of video and
time-lapse images, invite the school community to the “First Annual Microworlds Video
Festival.”
Movement of an Organism
Use the time-lapse feature to record movements of insects (e.g., mealworms, milkweed
bugs, lady bugs, ants).
Two videos of a honeybee scraping pollen from a male pumpkin flower in the pollen
basket on their back legs:
http://www.youtube.com/watch?v=8YiH9_yud40
http://www.youtube.com/watch?v=otXSdottnh4&feature=plcp
Germinating Seeds
Prepare seeds (e.g., corn, alfalfa, lima beans) for germination in a “baggy garden,” a
zipper bag container seeds planted on top of a staple with a moist paper towel. Use
the time-lapse feature to record the changes as the seed germinates.
Time-lapse videos of germinating corn (10 days) and alfalfa seeds (3 days):
http://www.youtube.com/watch?v=iFCdAgeMGOA
http://vimeo.com/groups/microstimelapse/videos/39106868
Larva Eating Behaviors
Use the time-lapse feature to record a classroom insect larvae eating and moving.
Time-lapse video (20:1 ratio): http://www.youtube.com/watch?v=BckbobrAyJE
The caterpillar in the video consumed the leaf in four minutes. The time-lapse video is 12
seconds.
Metamorphosis of an Insect
Use the time-lapse feature to record the metamorphosis of a classroom insect such as
an American Painted Lady butterfly. It takes seven to ten days for the pupa to mature.
Then, the adult butterfly emerges rather quickly. Once it emerges it takes several hours
before the adult butterfly can fly.
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Time-lapse video of a monarch butterfly emerging from a chrysalis:
http://www.youtube.com/watch?v=R5QH3bGF4uU&feature=related
Time-lapse video of the metamorphosis of a mealworm (darkling beetle):
http://www.youtube.com/watch?v=WTpNkcsKCak
Hatching Chicken Eggs
Use the time-lapse feature to record fertilized chicken eggs hatching. It takes about
three weeks for a fertilized egg to hatch in a classroom incubator.
Time-lapse video: http://www.msichicago.org/online-science/videos/videodetail/activities/the-hatchery/
Rotting Apple
Take a bite out of a delicious apple and set it on a plate. Use the time-lapse feature to
record evidence of the process of decay - oxidation reaction and growth of bacteria
and fungi. The apple begins to decay by turning brown within minutes after taking a
bite out of apple!
Time-lapse video: http://www.youtube.com/watch?v=IRiwXMeKoGk
Dissolving Crystals
Sprinkle a few crystals of salt or sugar on a surface. Add a drop of water and use timelapse video feature to record the particles flying off the crystals into the liquid solution.
Time-lapse video of salt dissolving in water (60:1 and 20:1 ratio):
http://www.youtube.com/watch?v=5JWosHgXFN4
Formation of Salt Crystals
Place small amount saturated salt water in a clear dish. Use time-lapse feature to
record the formation of crystals over four days.
Time-lapse video: http://www.youtube.com/watch?v=mvvNruJ-8LY
Phase Change: Solid to Liquid
Place an ice cube on a plate. Use time-lapse feature to record the ice cube melting at
room temperature over several hours.
Time-lapse video: http://www.youtube.com/watch?v=WgjksZoznuA
Phase Change: Liquid to Gas
Place a small drop of water on a plate. Use time-lapse feature to record the
evaporation over 1-3 hours.
Time-lapse video: http://www.youtube.com/watch?v=h_z98Uw5tWk
Adding Cold Water to Room Temperature Water
Empty a small plastic vial of refrigerated red-colored cold water at the top of a glass
filled with clear room temperature water. Use the video feature to record the
downward movement of the denser, red water over several minutes.
Video: http://www.youtube.com/watch?v=_Ww6BIy3nc0
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Capillary Action
Make a bold black water-soluble ink stripe on white paper towel. Add drops of water
on the black ink. Use the video feature to record the capillary action of water
separating black ink into component colors over several minutes.
Time-lapse video: http://www.youtube.com/watch?v=-fs5btFKdXA
GEMS Microscopic Explorations Learning Center Activities
Lawrence Hall of Science’s GEMS Microscopic Exploration is a teacher guide offering
ten learning station activities to promote students’ curiosity and scientific thinking. The
activities include easy-to-find materials for life, earth, and physical science microscopic
activities. You can read scientific information about the materials used for observation.
Here are brief descriptions of the 10 stations:
1. Up Close
Construct water drop magnifiers using 1-inch x 2-inch cover stock with hole punched
and transparent tape to observe small print in a newspaper. Drop water on top of nonsticky side of tape and observe the small print of newspaper through the water lens.
2. Fingerprint Ridges
Make impressions of fingerprints using pencils and a piece of transparent tape. Observe
the details of ridge patterns analyzed by forensic scientists to identify fingerprints.
3. Dots and Dollars
Observe and compare the dots on color newspaper photos, magazine pictures,
postage stamps, $5 bills, and other printed images. Understand how size and distance
between dots on color prints are combined to present the appearance of a range of
other colors.
4. Fabrics
Observe and compare a variety of fabrics (e.g., light-colored woven, knitted, and
pressed). Use the digital microscope to understand how fabrics are made.
5. Salts
Observe and compare crystals of various salts (e.g., rock salt, table salt, alum, boric
acid, Epsom salt) on cardboard “slides” (1-inch x 2-inch cover stock with hole punched,
transparent tape). Observe crystals form by adding Epsom salts to a crystal “sun
catcher.”
6. Sand
Observe and compare sand samples from several geographic locations based on the
color, size and shape of the sand grains. Sand samples can be found from the
International Sand Collector’s Society. The organization locates and marks on a map
the source of the sand samples.
7. Kitchen Powders
Observe and compare color, size and shape of seven white powders found in the
kitchen (e.g., table salt, cream of tartar, laundry detergent, baking soda, cornstarch,
white granulated sugar, flour).
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8. Small Creatures
Observe properties and structures dried insects (e.g., wings, eyes, jointed legs,
antennae) and mealworm larvae (e.g., eyes, segments, legs, bristles).
9. Brine Shrimp
Observe properties and structures (e.g., legs, head, eyes, gills, eggs sacs), and
movement patterns of adults, larvae and eggs of live brine shrimp (sea monkeys).
10. Pond Life
Observe and compare plant, animal, and one-celled organisms collected in a sample
of pond water.
(See Susan Brady and Carolyn Willard’s Microscopic Explorations in Teacher Resources.)
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Chapter 7 - Materials for Digital Microscopic Explorations
Observe and compare different materials that relate to life, earth, and physical science
curriculum. Here are various materials:
LIFE SCIENCE
1. Butterfly and dragonfly wings
2. Crickets
3. Dandelions - flower head, leaves
4. Dog and cat hair
5. Earthworm - Blood flowing in an earthworm. Using a 10x lens, place an earthworm in
a Petri dish with some water. Record the blood flowing.
6. Feathers - shaft and barbules; different types of feathers
7. Ferns - fronds and spores
8. Fingerprints - prints from different fingers, big toe and thumb, different people’s
fingerprints
9. Fish scales
10. Flowers parts - stamens, pistil
11. Flowers types - rose, forget-me-nots, tulips, foxglove
12. Fruit - strawberries, oranges, star fruit, kiwi
13. Granola
14. Human body parts - skin, hand, fingers, arm, leg
15. Insects - stages of development [e.g., larvae of mealworm (darkling beetle) and
wax worm (wax moth); structures (eye, antennae, legs, body parts – head, thorax,
abdomen)
16. Isopods - pill bugs and sow bugs
17. Lichens, liverworts, moss, mushrooms
18. Mealworms – behavior, movement and metamorphosis
19. Owl pellet - bones of the owl’s prey
20. Plant buds – not opened, beginning to open, and opened
21. Popcorn – popped and unpopped kernels
22. Rice - basmati, enriched white, long-grained brown
23. Seeds of foods - strawberry, peanut, sunflower
24. Shells - quahog, oyster, slipper, scallop, barnacle, periwinkle, razor
25. Spices - peppercorns, anise, dill seed, celery seed
26. Sprouts - fresh, whole, edible sprouts
27. Tree and shrub twigs
28. Tree bark - birch, sycamore, pine, oak
29. Tree clippings - cedar branch, holly
30. Tree leaves - conifer and deciduous leaves (e.g., dusty miller, sage, foxglove, ferns)
31. Tree seeds - maple, sycamore, acorn, walnut
EARTH SCIENCE
1. Crystal formation – saturated saltwater
2. Minerals - quartz, mica, iron pyrite
3. Rocks - granite, limestone, marble
4. Sands from different parts of the beach and geographic locations of the world
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5. Soil - sand, clay, humus
6. Water - property of density at different temperatures - cold water in room
temperature water. Position a low power lens to capture the side view of a clear
glass. Add a small plastic vial of red-colored cold water (iced) and empty at the top
of the glass filled with clear room temperature water. Record the downward
movement of the denser, red water.
PHYSICAL SCIENCE
1. Capillary action - Make a stripe with a bold black water-soluble ink marker on white
paper towel. Add drops of water on the black ink and record capillary action –
water separating black ink into different colors.
2. Clothing - coat, sweater, shirt, shoes
3. Crystals - dissolving of salt or sugar
4. Fabrics - microfiber cloth, burlap fabric, yarn
5. Kitchen powders – observe and compare similar white powders and crystals (e.g.,
table salt, cream of tartar, detergent, baking soda, cornstarch, white granulated
sugar, flour)
6. Paper and ink - printed text/photos from a book, newspaper, magazine, and
wrapping paper
7. Phase change - liquid to gas - drop of liquid water evaporating on a surface
8. Phase change - solid to liquid - small piece of ice melting on a surface
9. Salts - rock salt, table salt, alum, boric acid, Epsom salt
10. String - thread, cotton and nylon string
Using digital microscopes, students can observe and compare structures and properties
of matter, record time-lapse images of the growth and development of organisms, and
relate structure and function with materials contained in FOSS Full Option Science
System and STC Science and Technology for Children science programs. Here are
science kits and examples of observable materials.
PROGRAM
FOSS
STC
Animals 2x2 (K)
Organisms (1)
FOSS
Insects (2)
FOSS
Pebbles, Sand & Silt (2)
STC
FOSS
SCIENCE KIT (GRADE)
Plant Growth &
Development (3)
Structures of Life (3)
MATERIALS TO OBSERVE
goldfish, guppies elodea, mystery snails, ramshorn snails,
red worms, earthworms, pillbugs, sowbugs, fish food,
shells, potting soil, aquarium dip net
Lichen/moss mats, pine seedlings, elodea, cabomba,
guppies, pond snails, pillbugs, sowbugs, Bess beetles,
millipedes
butterfly, wax moth (waxworm), darkling beetle
(mealworm), milkweed bugs; screening, pabulum,
millet, shelled sunflower, soil
basalt, scoria, tuff, clay, cornstarch, humus, river rocks,
gravel pebbles, sand, sandpaper, screens
brassica (mustard) – different stages of development,
lima beans, soil, dried honey bees
crayfish; kidney bean, lima bean, pea, popcorn, corn,
sunflower, variety of fruits and vegetables, dry cat food,
gravel, nutrient powder, yarn
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FOSS
Water (3)
STC
Changes (3)
STC
Rocks & Minerals (3)
STC
Electric Circuits (4)
FOSS
Earth Materials (4)
FOSS
Ideas & Inventions (4)
STC
Ecosystems (4)
STC
Land & Water (4)
STC
Microworlds (5)
FOSS
Environments (5)
FOSS
Landforms (5)
profile of water drops on a penny, movement of cold
and hot water through room temperature water
clover, field corn, pea, radish, soil, brine shrimp eggs, fish
food, pabulum, antacid tablet, fabric, gravel, pepper,
kosher salt, steel wool pad, sugar cube, granular sugar
calcite, biotite, feldspar, fluorite, galena, gypsum, halite,
hematite, magnetite, muscovite, quartz, sulfur, basalt,
conglomerate, gneiss, granite, limestone, marble,
obsidian, pumice, sandstone, schist, shale, slate,
D-cell battery, paper fasteners, brass washer, wire
insulation, flashlight bulb, diode, fiberglass screen, wire
screen, brass screw, golf pencil, pipe cleaner, nail,
marble
gravel, calcite, feldspar, fluorite, gypsum, hornblende,
mica, quartz, basalt, cumberlandite, limestone, marble,
sandstone, sand, shell, coral pieces,
Fingers (fingerprinting), rubber bands, water-based
markers, fabric, netting
alfalfa, mustard, rye grass, algae mix, elodea,
duckweed, pond snails, guppies, crickets, isopods, salt,
fiberglass screen, soil
clay, humus, sand, markers, rubber bands, Velcro,
mustard seed, rye grass
one-celled organisms, blepharisma, vinegar eels,
feathers, fish scales, gelatin, grits, hay, marble,
microfiche, Epsom salt, table salt, sand, wire screen ,
poppy seed, year
darkling beetles (mealworm), isopods (pill bugs,
sowbugs), goldfish, elodea, gammarus, daphnia, pond
snails, duckweed
sand, clay, cotton swab applicator
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