Assessment – Physical Geology GLG 101 (GE Lab Science)
Spring 2008 – Croxen
Method:
Two sections of GLG 101 were selected for assessment. Eight questions were imbedded in the final exam
and students did not know which questions were being evaluated for assessment purposes. They did know
that there were extra credit questions and so were encouraged to answer all questions with equal effort.
Four themes or topics were considered for the selection of the questions. These topics were covered either
in lecture or lab.
1.
2.
3.
4.
Can the students take supplied values, set up the problem and properly do the math required to
determine the specific gravity of a mineral. (Quantitative Assessment)
Are students able to plot supplied values correctly on a graph, draw a line and determine the
magnitude of an earthquake based upon the intercept method. (Graphical Assessment)
On Monday, May 12, 2008 a severe earthquake occurred in China. I imbedded three questions to
test their awareness of current events in the context of the most recent subject we covered in class
prior to the final. The three questions covering these topics are: (Current Events Assessment)
a. Can students recognize the difference between a seismograph (the instrument that
records earthquakes and a seismogram (the actual printed or digital view of the wave
motions)? This distinction was pointed out in lecture and lab.
b. Do the students know in which country the earthquake occurred?
c. Could the students select from four choices the preliminary magnitude that was reported
in the news media (two of the choices were impossible magnitudes of absurdly high
values).
Are students properly reviewing for the final or, put in another way, are they utilizing their
resources? One way in which we reviewed for all semester exams was to go over the sample
questions at the end of each chapter we completed (the answers are in the back of the book). I
usually implied that several of those would be on each exam using much the same wording. I
selected three questions from the end of the earthquake chapter in their text book and placed them
in the final exam word for word. (Using Their Resources Assessment)
Results:
46 students took the final exam. The following table summarizes the eight questions and the percentage of
correct verses incorrect responses:
Quantitative Assessment –
Specific Gravity Determination
Correct
63%
Incorrect
37%
Graphical Assessment –
Magnitude from a nomograph
59%
41%
Current Events Assessment –
Seismogram vs. seismograph
26%
74%
Which country affected?
72%
28%
What was the magnitude?
61%
39%
Using Their Resources Assessment –
Energy vs. magnitude comparison
31%
69%
Shallow focus is most dangerous
22%
78%
Definition of earthquake intensity
49%
51%
Outcomes and Selected Questions:
Quantitative Assessment – It is clear that most students are able to take supplied values and, using a word
problem, construct an equation to solve for mineral specific gravity. The rigor is not necessarily with the
math but skewed more towards the concept. If the student sets up the word problem incorrectly or switches
the values around, they will compute an incorrect value. I see no real change in the manner that specific
gravity is discussed or measured in lab. I have the students work in groups (limited by the number of
scales) during lab determining mineral specific gravities. What may be useful in the future is to ensure every
student takes the time to measure and calculate a specific gravity.
The specific gravity of a mineral can be determined by its weight in air divided by the difference
from its weight in air minus its weight in water. If the weight in air equals 18.27 grams and the
weight in water equals 11.73 grams, than what is the approximate specific gravity?
A.
B.
C.
D.
E.
0.36
0.64
1.55
2.79 (answer)
6.54
Graphical Assessment – It appears that students struggle with plotting values on graphs. This question
requires the students to consider two sets of units: millimeters and seconds. If they are not careful they may
plot the seconds and millimeters on the wrong sides of the graph. I continue to stress the importance of
reading what units are displayed on each graphical axis. Again, maybe repetition is the only way to ensure
the majority of students understand and can read graphs.
On the following nomograph, what would the magnitude be for an earthquake with an
amplitude of 25 mm and a P-S wave time of 5 seconds?
A.
B.
C.
D.
E.
4.5
4.0
3.5 (answer)
3.0
2.5
Current Events Assessment – The results of these nested questions was a bit of a surprise. The first
question was really testing their vocabulary (an important component of any science course). Moreover, I
do have many students whose primary language is not English. In class I do emphasize the difference
between a seismograph and seismogram. I often use the analogy of using a telegraph to send a telegram,
hoping this will stimulate their word association. We also use seismograms in lab activities. Despite all this
help, students still confuse the terms. I need to confer with a colleague in the ESL or English programs to
come up with a better strategy for word association.
On May 12, 2008 a powerful earthquake occurred. Below is the image captured from the seismic
instrument in the geology classroom at AWC’s main campus. What is this earthquake record called?
A.
B.
C.
D.
E.
a tsunami
a seismogram (answer)
a heliograph
a seismograph
a sonogram
The other two questions about which country the earthquake occurred and the first reported magnitude met
with better success. Anyone keeping themselves apprised of global events would have seen or heard of the
severe earthquake in print, radio, internet or television media. I didn’t expect the magnitude question to
have as much success, and I did include two of the four possible responses as unreasonable magnitude
values that are not possible as was discussed in class. I plan to continue emphasizing current events
related to geology and I may start a project next semester that requires students to find relevant geological
events in the current media and report them in class on a weekly basis.
Since this is a current event, in which country did the above earthquake occur?
A. Sumatra
B. Iran
C. Chile
D. China (answer)
What was the preliminary magnitude of the earthquake?
A. 7.8 (answer)
B. 8.8
C. 9.8
D. 10.8
Using Their Resources Assessment – It continuously amazes me how many students don’t get the full value
out of their required course materials. I stressed all semester to review the end-of-chapter questions in
preparation for each exam, including the final. It is apparent that most students didn’t bother the read
through the sample questions and even look up the correct answers for the chapter on earthquakes. The
topics of the three selected questions were covered in lecture and placed on the exam word for word. I plan
to continue this effort and may consider assigning an end-of-chapter question to each student who is to
bring back the correct answer and explain why the following class period.
It would require how many earthquakes with a Richter magnitude of 3 to equal the energy released in
one earthquake with a magnitude of 6?
A.
B.
C.
D.
E.
9
30
250
27,000 (answer)
2,000,000
With few exceptions, the most damaging earthquakes are:
A.
B.
C.
D.
E.
deep focus
caused by volcanic eruptions
those with Richter magnitudes of about 2
shallow focus (answer)
those that occur along spreading ridges
The qualitative assessment of the damage done by an earthquake is expressed by:
A.
B.
C.
D.
E.
intensity (answer)
dilantancy
seismicity
magnitude
liquefaction