Introduction
I tried something
different this year during my unit on ozone
depletion. . . . and it worked real well! I
ordered a bunch of ultraviolet sensitive beads
from a company called “Educational
Innovations” (see Hot Link below). The beads
change from white to colored when exposed
to the Sun’s ultraviolet rays. They come in
packages of 240 for $6.95.
Project
Here’s what I did. I gave
each student a reclosable snack bag with 12
beads (4 that turn yellow, 4 that turn red, and 4
that turn blue). Next, I explained that each of
them would need to design, and carry out an
experiment to find the answer to one of the
questions listed below. The students were
given 2 weeks to complete the project.
1. Do clouds block some or all UV rays?
2. Is old sunscreen as effective as new
sunscreen?
3. Do T-shirts block some or all UV
rays?
4. Does windshield glass block some or all
UV rays?
5. Are all of the windows in a car equal when it
comes to blocking UV rays?
6. Does SPF 30 sunscreen give twice the
protection of SPF 15?
7. So UV filtering sunglasses really block UV
rays?
8. Is exposure to UV rays at midday as great
as exposure to UV rays at other times during
the day?
9. Is sunlight reflected from a white surface as
dangerous as direct sunlight?
10. Does water reflect all or some UV
rays?
11. Are UV rays able to travel through
water?
12. Students were also given the option of
coming up with their own question at my
discretion.
Scoring
A. Question and
hypothesis: 2 points
B.Description of
experiment: 5 points . . . Someone else
should be able to repeat the experiment,
using your
instructions.
C.Data/observations: 5
points
D.Conclusion: 3 points
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