Research: Science and Education
Students’ Self-Assessment in Chemistry Examinations Requiring Higher- and Lower-Order Cognitive Skills
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Uri Zoller,* Michal Fastow, and Aviva Lubezky Department of Science Education–Chemistry, Haifa University–Oranim, Kiryat Tivon 36006, Israel Georgios Tsaparlis Department of Chemistry, University of Ioannina, GR-451 10 Ioannina, Greece
The development of students’ higher-order cognitive skills (HOCS) in the context not only of the specific content and processes of the science disciplines but also of the interrelationships of science, technology, environment, and society has become one of the most important goals of chemistry and science education (1–3). However, although the teaching, learning, and assessment of these skills are advocated by many, they are rarely actually pursued in college chemistry teaching. A shift from the dominant lower-order cognitive skills (LOCS) to the HOCS orientation in chemistry teaching requires a drastic change not only in teaching and learning, but also in assessment strategies consonant with this. Since very few exams that push beyond tasks of information retrieval, relabeling, or recognition or focus beyond basic skills in the subject matter are currently used, the implementation of assessment methods that attempt to capture more complex aspects of learning (i.e., HOCS) is clearly in order (1, 4). It is well established that in self-regulated learning (the fusion of “skill” and “will”), students manage their learning not only by use of cognitive, meta-cognitive, and volitional control strategies, but also by use of motivational strategies (5). This requires them to take more responsibility for their learning by assuming an active role in the learning process, including self-assessment of their own progress. If we engage students as partners in activities involving selfawareness and self-evaluation of their test performance and progress in learning, they can not only enhance their strengths and reduce their weaknesses but also learn in greater depth and develop their HOCS-requiring capabilities. We explored the possibility of involving students in HOCS-promoting processes within chemical teaching via self-assessment and self-grading of HOCS-oriented chemistry examinations. Our research questions were: 1. Can students in a college chemistry course perform self-assessment? 2. Is their assessment compatible with that of their professors? 3. Are the students confident in doing this self-assessment?
This paper constitutes a research-based response to the above questions. It is based on the following selected exam
questions, which were graded by both students and their professors in freshman general chemistry classes in Israel and Greece. Exam Question One of the best ways of checking the purity of PCl3, which is used in the manufacture of saccharin, is to compare the mass spectrum of a sample with that of pure PCl3 . Given: that chlorine has two naturally occurring isotopes (35Cl and 37Cl, relative abundance ~75:25%, respectively), whereas phosphorus has just one (31P). Q1. In your opinion, is the given relative abundance for the chlorine atom (75:25%) relevant to the method here presented for checking the purity of PCl3? Explain. Q2. How many molecular peaks and which specific masses do you expect to find in the mass spectrum of pure PCl3? Is the emphasis on pure important? Explain. Q3. Do you expect the number of peaks in the mass spectrum of pure PBr3 to be the same as that of pure PCl3? Explain. Q4. Do 10 grams of PCl3 contain more, the same, or fewer atoms of chlorine than the number of bromine atoms in 10 grams of PBr3? If you think that the number is the same, then explain why; if not, calculate the weight of PBr3 which contains the same number of bromine atoms as the number of chlorine atoms in 10 grams of PCl3. Q5. Which, the atom or the ion, in each of the following three pairs: P+, P; Cl, Cl ᎑; and Br, Br᎑, do you expect to have the lower ionization potential? Explain your ordering.
The first parts of Q2, Q3, and Q4 are considered LOCS; Q1, Q5, and the last part of Q2–Q4 are HOCS. Results Students’ appraisal of their extent of understanding and of their capability and confidence in self-assessment and assessment of peers with respect to the take-home exam questions (Q1–Q5) were evaluated using a specially developed Likerttype questionnaire, SAQHOCS (3). The results of the Israeli students’ evaluation of their capability and confidence in selfassessment and assessment of peers indicate that they believe
W An extended version of this article is available on JCE Online at http://jchemed.chem.wisc.edu/Journal/issues/1999/Jan/ abs112.html.
*Corresponding author. Email:
[email protected].
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Journal of Chemical Education • Vol. 76 No. 1 January 1999 • JChemEd.chem.wisc.edu
Research: Science & Education
that “to a reasonable extent” they are capable of self-assessment and feel confident in this process (x¯ = 2.95 on a 4–1 scale). Similarly, they believe in their capability of assessing their peers and have confidence in doing so (x¯ = 2.6). These findings are rather encouraging. Selected results comparing the students’ self-grading of their first-semester midterm take-home exam with the grading of the same chemistry examinations by their professors are given in Table 1. The main findings are that the gaps between the students’ self-grading and their professor’s grading of LOCS questions (e.g., Q3) are fairly small and statistically nonsignificant, whereas the gaps in the grading of HOCS questions (e.g., Q1) are relatively large. We conclude that students’ self-assessment of chemistry exam questions requiring LOCS is compatible with that of their professors, but that requiring HOCS is not. These results suggest that the more familiar students are with a problem or the deeper their conceptual understanding of the problem is, the better are both their performance and the matching of their self-assessment with the assessment of their professors.
students’ HOCS capability is a major objective in the reform of science and chemistry education, HOCS-oriented teaching and learning strategies should become the focus of the teaching–learning process. Students’ self-assessment that is consonant with the HOCS orientation should, therefore, become routine in chemistry and other science teaching. It should be done and can be done. However, for students to become capable and confident in self-assessment they should be encouraged and guided by capable, enthusiastic “HOCS teachers” to become autonomous learners. We are currently developing and implementing science courses within which students are actively involved in HOCS-demanding problem solving. There are indications that these students gradually develop the capacity for self-assessment of exam questions that require HOCS. Literature Cited 1. Zoller, U. J. Chem. Educ. 1993, 70, 195–197. 2. Benchmarks for Science Literacy: Ready for Use; AAAS Project 2061; Oxford University Press: New York, 1994. 3. Zoller, U.; Tsaparlis, G.; Fastow, M.; Lubezky, A. J. Coll. Sci. Teach. 1997, 27, 99–101. 4. Bunce, D. M.; Bowen, C. W.; Cardula, F.; Gabel, D.; Greenbowe, T.; Jones, L.; Nakhleh, M.; Nurrenbern, S.; Robinson, W.; Phelps, A.; Sawrey, B. Testing for conceptual understanding on standardized examination. Paper presented at the National Meeting of the ACS; Anaheim, CA, March 1995. 5. Garcia, T.; Pintrich, P. R. Self-schemes, motivational strategies and self-regulated learning; paper presented at the Annual Meeting of the Am. Res. Assoc.; Atlanta, GA, April 1995.
Conclusion Although there is a gap between student self-assessment (overestimation) and professors’ assessment of performance on HOCS-type (but not LOCS-type) chemistry exam questions, the potential for self-assessment does exist. Nevertheless, persistent and purposeful HOCS-oriented chemistry teaching and learning work needs to be done. Since the development of
Table1. Students' and Professors' Grading of Questions on a Midterm Chemistry Exam Question Country N Israel
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Q1 S
P
S
61.1
89.0
∆
80.2
Q2
19.1 Israel
28
82.5
64.8
17.7 Greece 56
60.8
37.6
23.2
Q3 P
∆
84.4
4.5 87.8
87.0
0.8 57.9
26.6
31.3
S
Q4 P
∆
S 96.8
87.4
93.8
82.2
5.2 62.2
61.1
1.1
S
93.3
88.3
∆
89.6 92.9 ᎑3.3
Q5 P
3.5 85.0
8.8 92.2
86.3
5.9
S
77.3
89.4
∆
11.0 79.4
65.9
13.5 76.6
Overall P ∆
P
48.4
28.2
81.7
7.7 85.5
77.0
8.5 64.1
47.7
16.4
NOTE: Grading was from 0 to 100. S represents mean self-grading score of students’ grade and P represents the professor’s mean grade of the students. A positive ∆ (S – P) indicates an overestimation by students compared with professors; the single negative ∆ indicates an underestimation.
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