BACKGROUND:
Many science concepts
are built on the objects that children cannot see, including blood
circulating through small pores in bones; microorganisms that are in and
on your body; chloroplasts as the center of photosynthesis in plants;
and minerals that make up rocks. The microworld is complex and all
larger structures and organisms depend on it. This world can seem
very strange and mystical, until you make an effort to look at it closely.
The microworld includes the living within the kingdoms of plants, protozoa,
animal, fungi, and bacteria and the non-living like viruses, minerals,
micro-chips, and many other objects. Children will believe that this
"micro-magic" exists of they can experience the joy of seeing this world.
The microscope allows this to happen! It is important for children
to see this world to understand the components of the earth and biological
systems.
 We recommend
either the Swift GH Microscope
or a Prism Microscope for use with elementary students. The Swift GH is
more versatile but the Prism is very cost effective. Familiarize your students with
the microscope by carefully going over some basic principles with them.
Make sure students realize that one eye should be closed when they look
through the optic tube. Have them cover one of their eyes and have
them focus on an object. Four younger children you might want to
have a set of "pirate patches" to make it fun. Have the students
find out which eye is more comfortable. Also, children do not realize
that there is a distance that the eye should be above the eyepiece.
Their eye should be near the eyepiece, but not resting on the lens.
Have them find the correct spot. They can look at a specimen with
or without glasses, depending on whether they are comfortable or not.
Focusing can be a frustrating
experience for students. For lower primary students they can use
the arm to focus up and down, without playing with the focusing mechanisms.
Upper primary students can learn how to recognize the correct "working
distance" from an object. Usually, the lower the magnification the
farther the object needs to be. Have the students measure the distance
from the objective to the object. If you are using the 2.5x objective
the distance from the object is 5.5 cm. Care and patience must be
emphasized with students. Once they know approximately how far to
rack the tube up and down, they will not get frustrated.
PROCEDURE:
- Read The Naked Eye to children. Make sure you go over some
of the words in the storybooks by reading it first and then go back through
the story and identify words that may be new to kindergartens. Usually
the picture helps explain the new word.
- The object
of this lab is for students to decide whether the microscope or a hand
lens makes an object more distinct. Students will "vote" at each
station whether the hand lens or the microscope makes the object larger.
Remember, you must have two identical objects if you did not purchase the
kit. Use the same kind of magnifier at each station.
- Review the use of the
Swift GH or Prism microscope.
- Students may have difficulty
in looking through a microscope. One eye should be closed and the
opened eye should look through the tube. You may want to use "pirate
patches" over one eye or have the students put their hand over one eye.
This helps students see more easily through the microscope. Do not
have the students adjust the microscope. Focus the material for students.
Remember the 2.5 objective is about 5.5 cm away from the object.
- Give students 15 LARGE
and 15 VERY LARGE strips of paper to be used for voting. Emphasize
that you want your students to analyze how clear the image is.
- Have students go to
different stations that are prepared with two similar items (you can limit
the stations but we suggest 15). Put one of the items under the microscope
and examine the other item with the hand lens. On the microscope
use the reflected light option. Children at this age have trouble
looking at a thin section. If you have not purchased the kit, select
items that the children are familiar with like feathers, sand, fabric,
seeds, dirt, or any other available items.
- After looking at both
items, have students "vote" on the hand lense or microscope that
makes the item look the largest (VERY LARGE) and the instrument that
they think is not the largest, have them put (LARGE).
- After the students have
been to all the stations, go to each station and count the number of votes.
Hopefully all the microscopes will win. Discuss how the microscope
makes objects more distinct and shows more detail.
- If you do not have the Swift-GH microscope or Prism
Microscope, you may want to use another hand lens.
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