Grading To Reward Accumulated Knowledge R. Daniel Bishop, Jr.
Colorado State University. Fort Collins, CO 80523 Students differ greatly in the amount of time required to assimilate a body of knowledge such as that represented by most chemistry courses. Some students grasp new concepts quickly and have little trouble applying these principles. Such students maintain a high level of achievement throughout the course and are usually our "A" students. Most students require more time t o understand and use new material. Although such students have finally mastered the subject, it is too late for this achievement to be fully reflected in their grades. Keeping these students motivated throughout the semester while continually penalizing them (through low exam erades) is a dauntine challenge. Those students -. and do well on tLe final exam walk away with who a course grade that does not accuratelv reflect the final level ofknowledge and skills attained. Unfortunately, too many students have "given up" on the course by the final. I t is not uncommon for the final exam averaee to he well below the averages for the unit exams takenuduring the course. For example, a sampling of three introductory chemistry classes recently taught a t CSU showed the final exam average to he 4 to 5 percentage points lower than the overall average . of the unit exam scores ineach class. In an attempt to remedy some of these problems, I recently taught three classes using a grading scheme that encouraces students to keep striving throughout the entire course dhile eliminatine - - ~ - ~ ~ " anv oenalties associated with a "slow" learning curve. In all three classes, the final exam averages were actually higher than any of the four hourly exams. Athough exam questions on the hourlies and final covered the same material. I attemoted to make them sufficiently different to ensure' that student improvement would not be the result of rote memorization. Two examples showing the correspondence between hourly exam questions and final exam ouestions are shown a t the end of this article. I felt'that my students on the whole had achieved a higher level of understanding of the course material than in other
Summary of Grade and Exam Score Improvements Rerultlng from Allowlng Flnal Exam Secllon Grades To Replace Lower Hourly Errm Grade*
Number of Students Students with improved Letter Grades Percent Improvement on Final Exam Scores (Final Exam Section Avg. vs. Hourly Avg.) Section I: Section II: Section III: Section IV:
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492
A
Journal of Chemical Education
83 21 (25%)
39 9 (23%)
6.8% 6.4% 5.4% -0.1%
5.8% 20.4% 7.4%
9.5%
courses I have taught over the previous 10 years. Between 23% and 40% of the students earned a t least one letter grade higher than if the course had been taught using the traditional grading scheme. And this "grade inflation'' was obtained without anv comoromise of achievement standards. The final grades mire accurately reflected what the students had learned bv the end of the course rather than evaluatine the speed wit6 which they were able to learn new conceptsEach course had four 100-~ointhourlv exams and a 400point final. The final was diGided into four clearly identifiable sections, with each section corresponding to the material covered by one of the hourly exams. If a student's grade on any section of the final was higher than hisher grade for the corresponding hourly exam, the final exam for that section also replaced the hourly exam grade. (The reverse process, having an hourly exam grade replace a section grade on the final, was not allowed). In this way, if a student did better on all four sections of the final than on hourly exams, the student's entire grade was based on the final exam. On the other hand, if all four section grades on the final were lower than hourly exam grades, no adjustments were made. In this case, grading was simply traditional, with the final exam counting for 50% of the overall grade. ~~
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This approach establishes course grades that more accurately reflect what the students know when they have completed the course, while avoiding the psychological barrier of having the final exam be the only exam given in the course. I t also gives the student something to work for throughout the entire semester, even if the hourly exam grades are poor. One nontraditional student in my introductory chemistry class did not begin to understand the concepts until two-thirds of the semester had ~ a s s e d at . which time he Doured on the effort. He obtaineda 11%bn the final, converting a solid "F" average to a "C" for the course. Furthermore, having experienced the thrill of accomplishment, this student was justifiably proud of that "C". In general, student response to this approach toward grading was very favorahle. An added advantage for the instructor is that make-up exams can be eliminated without penalizing the student. Students also had the option of skipping any (or all) of the hourly exams, although they were strongly discouraged from doing this. In such cases, the student's performance on the corr
