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the data. The writer took one class for the try out group. The test consists of 5 passages which contained 50 questions. The students had
to finish 50 items objectives type test multiple- choice in 90 minutes. After the students finished the test, the answer sheet was turned into the
score. The multiple choice test scored 1 for the right answer and 0 for the wrong answer.
3.6.1.1 Level of Difficulty
As mentioned in the chapter III, there are five categories of level of difficulty: they are very difficult, difficult, medium, easy, and very
easy. After computing 50 items of try out test, there was 15 items were easy items number 1, 2, 5, 6, 9, 10, 12, 15, 16, 19, 22, 25, 26, 30, and
32 , 34 items were medium items number 3, 4, 7, 8, 11, 13, 14, 17, 18, 20, 21, 23, 24, 27, 28, 29, 31, 33, 43, 35, 36, 37, 38, 39, 40, 41, 42, 43,
44, 45, 46, 47, 48, and 50 and 1 item was difficult item number 49. The next step the writer calculated the discriminating power in
order to determine how well each item discriminated between high – level and low – level examines.
3.6.1.2 Discriminating Power
The discrimination index of the item indicates the extent to which the item discriminated between the testers. Separating the more able testers
from the less able, the index of discrimination tells us whether those students who perform well on the whole test tend to do well or badly on
each item in the test Heaton in Ernawati, 2003:31 . There are four
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categories of the discrimination index; such excellent, good, satisfactory, poor. After try out test was administrated, the test items
which did not fulfill the requirements of the valid test were invalid and they had to be rejected. Items number 9, 19, 20, 31, 35,41, 49, and 50.
3.6.1.3 Procedure of Experimentation
Conducting an experiment always required some steps which had to be done in a chronological order. The following steps were taken by the
writer as she worked on the experiment, first is to choose the second year students of senior high school SMA N 1 Pegandon, Kendal as the
population; take one group of the population as the experimental group; conducted the real experiment. After getting the students works, the writer
scored the student’s works; the writer compared the means by applying the t-test formula; consulted the t value with the critical t value at the 5 0,
5 alpha level of significance.
3.6.1.4 The Activities of experimental group
