Students’ learning can be measured by different procedures. One of these procedures, which is widely used by teachers in the classroom, is the achievement test. Achievement tests are commonly used for assessing students’ learning. They are also considered as a tool for enabling teachers to judge whether students have mastered the taught skills and knowledge, thus to find out whether the planned behavioral objectives are achieved.

Educators (e.g., Brown, 1987; Darwazeh, 1997a ) have classified achievement tests into two major types: the essay type, and the objective one. An essay type test is defined as a tool which requires students to write the answer in their own words (e.g., How do colds spread ? ), whereas the objective type test is defined as a tool which requires students to recognize and mark the correct answer from a number of options (e.g., which disease of the following has the same symptoms to the cold ? a) Influenza b) Fever c) Cancer d) Heart disease ). 

Good achievement tests are supposed to measure different levels of learning. Bloom (1956), for example, classified six hierarchical categories according to the cognitive process they need. Descriptions of the major categories in the cognitive domain are: (1) knowledge levels in which students are required to memorize facts and knowledge (e. g., who was the winner of the 1954 Nobel prize for chemistry ? ), (2) comprehension levels in which students are required to interpret information in their own words (e.g., why can't a doctor tell if a person has a cold or a flu ? ), (3) application levels in which students are required to use what they have learned in a new situation (e.g., do you think that you should or should not shake hands with some one who has cholera ? ), (4) analysis levels in which students are required to break down the instructional task into its components (e.g., what elements does water consist of ?), (5) synthesis levels in which students are required to make some inferences and come up with conclusions (e.g., what are the main ideas that the lesson talks about?), and (6) evaluation levels in which students are required to judge and value the merit of the learned materials, and make a decision (e.g., do you think that your teacher has explained the lesson of "The Common Cold" in terms of its major ideas clearly ? ) ( See, Darwazeh, 1987, 1997a; Martin et al. 1994, p. 160-171; Hill, 1982, pp. 181-200).

David Merrill (1983), on the other hand, has proposed different kinds of taxonomies based on two dimensions: 1) the type of instructional content, and 2) the level of instructional performance-  . The instructional content type is defined as all knowledge and information that are required by students to learn during their learning. Merrill ( Ibid ) had classified content type into four types. They are: (1) concepts, (2) principles, (3) procedures, and (4) facts (See, Darwazeh, 1995, for definition of each ). 

Whereas, the level of instructional performance is defined as the student's behavior which he /she shows after the instructional process has taken place. Merrill had classified the performance levels into four levels of learning. They are : 

1- Remember - an - Instance level (RI) in which students are required to recall or recognize a specific information, such as to remember names, dates, symbols, labels, etc. (e.g., who was the winner of the 1954 Nobel prize for chemistry ?). 

2- Remember - a - Generality level (RG) in which students are required to remember general information and basic ideas, such as recalling a definition of principle, concept, or procedure (e.g., what is the main difference between cold and influenza ?).

3- Use - a - Generality level (UG) in which students are required to apply a generality to a new instance (e.g., is cancer a contagious disease ? ). 

4- Find - a - Generality level (FG) in which students are required to derive or invent a new generality from new instances that students haven't seen before (e.g., derive the principle of lightning by manipulating these new phenomena?) (see, Darwazeh, 1997b, p.110-115; Hill, 1984, p.183 for more details).

Educators (e.g.; Darwazeh, 1996 ) believe that presenting different levels of adjunct questions during instruction will induce different levels of students’ learning. Adjunct questions could be presented on different levels according to the cognitive processes they need. These levels usually vary from simple (Remember - an - Instance RI and Remember - a - Generality RG) to complex ( Use - a - Generality UG ) and Find - a - Generality FG ). Simple level questions such as (RI, RG) usually require low cognitive processes, whereas complex level questions such as (UG) usually require high cognitive abilities. Some studies have supported this hypo- thesis Watts & Anderson (1971), and Shavelson et al. ( 1974 ) , for example, found that the subjects who received high level questions in which they were asked to apply certain principles to new instances during instruction performed significantly better on the posttest than the subjects who received low level questions requiring them to recall specific information. Rayan (1973) concurred with the above results and emphasized that asking different levels of adjunct questions will promote different levels of learning. He found in his study that high - level questions lead to a greater effect than low - level ones on the students’ learning. Winne (1979), on the other hand, could not find a significant difference between the effect of high versus low - level questions in terms of their effects on students’ learning.

Educators (Darwazeh, 1982; Hudgings, Dorman, Harris, 1979; Loring, 1987; etc.) also believed that the effect of adjunct questions is influenced by different levels of students’ ability. Martin et al. (1994) summarized Barnes’ study (1978) in which he investigated the interaction between the levels of questions - high levels (UG, FG) and low levels (RI, RG) - and the levels of student's ability (high versus low). Results showed that there was a positive relationship between higher level questions and higher level student's ability. 

Darwazeh (1982) on the other hand, found a significant interaction between the position of questions and student's ability which indicated that pre-questions enhanced the learning of low ability students, whereas post questions enhanced the learning of high ability students. Hudgings, Dorman, and Harris (1979) also had found similar results which indicated that post-questions enhanced learning of high ability students, whereas pre-questions did not make a difference between low or high ability students. 

In the current study, the researcher intended to investigate different types of questions: essay questions versus objective ones and three different levels of questions: Remember- an- Instance, Remember -a- Generality, and Use - a - Generality, on three levels of learning (RI, RG, UG) based on Merrill’s taxonomies of learning. The Find - a- Generality level (FG) will not be included in this study because it has low relevance to most classroom objectives, and because "Merrill" has not yet adequately specified the nature of questions for the Find- a - Generality (FG) level ( See, Darwazeh, 1982).

Different levels of student's ability ( high, medium and, low) that were measured by the General Secondary Examination (Tawjihi exam) average will also be studied in the current study. Thus, the researcher will classify student's ability into three levels: high level ability students are those whose average is 85% and more; medium -level ability students are those whose average ranged from 84 % to 75 %; and low- level ability students are those whose average is 74% and below. This classification will be based on the general average in the Tawjihi exam, as we have just mentioned.

Research Problem and Purposes TOP

It is known that students are always afraid of tests which assess their knowledge that they are taught in classrooms. Many students attribute their low achievement to the types of tests that the teachers use for evaluation.

Teachers are also puzzled as to what type of questions they have to use in measuring their students’ learning. On the other hand, previous studies which have investigated essay versus objective type tests did not differentiate among the different levels of learning that the posttests may measure.

Therefore, the purpose of this study is to investigate the effect 
of question types (essay versus multiple-choice ), and question levels (Remember - an -Instance (RI), Remember - a- Generality (RG), and Use - a- Generality (UG ) on three levels of learning based on Merrill’s taxonomy (RI, RG, UG). Student's ability levels ( high, medium, and low ) will also be investigated in this study by using Three -Way Analysis of Variance (ANOVA ) (See the method section ).

Significance of the study TOP

The Findings of this study are expected to be of great importance for educators in general and teachers in particular who are interested in testing and evaluating students’ learning. Therefore, the most significant aspects of this study are offering insights to 
* the type of questions (essay or objective) which most affects students’ levels of learning,

* the level of questions (RI, RG, or UG) which most affects students’ levels of learning, and 

* the student's ability (high, medium, or low) which most affects students’ levels of learning.

Research Questions TOP

The research questions are the following:
1- Which type of questions ( essay or objective ) has more effect on students’ overall learning ?

2- Which level of questions ( RI, RG, or UG ) has more effect on students’ overall learning ?

3- Which level of ability ( high, medium, or low ) has more effect on students’ overall learning ?

4 - Is there an interaction between question types ( essay versus objective) and question levels (RI, RG, UG ) on students’ overall learning ?

5- Is there an interaction between question levels ( RI, RG, UG ) and student's ability ( high, medium, low ) on students’ overall learning ?

6- Is there an interaction between question types ( essay versus objective ) and student's ability on students’ overall learning ?

7- Is there an interaction between types and levels of questions and student's ability on students’ overall learning ?

8- On the posttest, is there a significant difference between the control groups’ performance which didn't receive questions during the experiment and the experimental groups’ performances which manipulated questions during the experiment ?

Research Hypotheses TOP 

The researcher postulated the following eight null hypotheses:

1 . There are no significant differences at ( 0.05 ) a priori level of significance between the essay questions and the objective ones on all levels of learning ( RI , RG , UG ).

2 . There are no significant differences at ( 0.05 ) a priori level of significance among the three levels of questions ( RI, RG, UG ) on all levels of learning.

3 . There are no significant differences at ( 0.05 ) a priori level of significance among the effects of the three levels of the student's ability ( high, medium, and low ) on all levels of learning.

4 . There is no significant interaction at ( 0.05 ) a priori level of significance between question types and their levels on all levels of learning . 

5. There is no significant interaction at ( 0.05 ) a priori level of significance between question types and student's ability on all levels of learning.

6. There is no significant interaction at ( 0.05 ) a priori level of significance between question levels and student's ability on all levels of learning.

7. There is no significant interaction at ( 0.05 ) a priori level of significance between question types, levels, and students’ ability on all levels of learning. 

8. There is no significant difference between the control groups’ performance compared with the experimental groups’ performance.