Medical Technology: organ harvesting and Transplants

For the 2008-2009 school year, fuels were tested in our
school’s small Kubota tractor with a diesel engine. This is a
perfect, real-life application for the fuel the students make.
The Kubota tractor was modified with a second small fuel
tank (approximately 100 mL) for our biodiesel and a valve
to switch between tanks. This allowed starting and stopping
the tractor using petroleum diesel and enabled students to
switch over to biodiesel for data collection.
Unit of Instruction Results
The SI index was calculated using the pretest and posttest
results to determine the effectiveness of the unit of
instruction. Considering that the test was comprised of
twenty multiple-choice and four completion questions,
after factoring in guessing, a realistic high of .79 could be
expected. The results showed an average SI score of .51.
The SI scores indicate a good unit of instruction, perhaps
requiring minor revisions on selected areas. Table 2 shows
the calculated SI score for each test item, the average SI
score, and the number of students correctly answering each
item before instruction (Rb) and after instruction (Ra).
Test items 4, 6, 19, 20, and 24 all received SI scores below
0.30. These items were examined to determine where
the unit, instruction, or evaluation could be improved.
Item 4—instruction on the item’s distracters, was not
thoroughly covered, but has been enhanced in the unit to
increase student comprehension. Item 6 received the lowest
number of correct answers after instruction. It is believed
the material was covered; however, the question may have
been confusing to the students. The stem of the item was
originally written in negative form, and will be rewritten
in positive form. The next time the unit of instruction is
taught, the SI will be recalculated to see if this resolves the
problem. Item 19 was a general safety question. Nineteen
students answered correctly on the pretest, with everyone
answering correctly on the posttest. As a safety item, this
was prior knowledge for many of the students, resulting
in a low SI score. Since everyone answered the question
correctly on the posttest, no changes were made to the
lesson plans. Item 20 was a difficult item. Students should
not have had any prior knowledge and should have received
very few correct answers on the pretest. The test item was
rewritten to minimize guessing. The unit of instruction
did not fully cover Item 24. The activity sheet for testing
the biodiesel has been modified to better cover this
concept. Utilizing this process, each time the unit is taught,
improvements can be made.
Positive feedback on the unit of instruction was received
from a variety of observers and participants. Students
were excited to learn about these alternative fuels and to
Type Item # Category Ra Rb SI
Fill-in-blank 1
18 2 0.70
M/C 2 Renewable 12 5 0.30
M/C 3 fuels 16 7 0.39
M/C 4 15 9 0.26
M/C 5
21 0 0.91
M/C 6 9 3 0.26
Fill-in-blank 7 21 0 0.91
M/C 8 22 7 0.65
M/C 9 Ethanol 22 9 0.57
M/C 10 21 6 0.65
Fill-in-blank 11 15 0 0.65
M/C 12 14 3 0.48
M/C 13 19 8 0.48
M/C 14 Internal 20 7 0.57
M/C 15
Combustion
20 5 0.65
M/C 16
19 9 0.43
Fill-in-blank 17 18 0 0.78
M/C 18 21 13 0.35
M/C 19 23 19 0.17
M/C 20 Biodiesel 19 16 0.13
M/C 21 13 2 0.48
M/C 22 19 9 0.43
M/C 23 22 6 0.70
M/C 24 11 6 0.22
Table 2. Sensitivity to instruction (SI) index scores.
Average 0.51
continue experimenting. Parents insisted their children
take the class because of the importance and timeliness of
the topic. Counselors reported many positive comments
received from girls who had participated in the alternative
fuels unit. School administrators were excited to have a
teacher creating a new unit on current issues. The regional
newspaper was impressed and published a feature story
covering the alternative fuels unit on the front page with
pictures of students making biodiesel (Nelson, 2008).
All reports and feedback indicated strong interest and
excitement for the unit of instruction on alternative energy.
24 • The Technology Teacher • April 2010