What are typical grades in the Freshman Chemistry sequence (CHEM 1211, CHEM 1212)? The UGA general chemistry program uses a “contract” system for assigning grades. Details about what total “points” or percentage of them is required to earn a specific grade appear in each course’s syllabus. There is no limit to the number of each grade; this depends on how each student performs. Other institutions use a “curve”, a system based on the arithmetic mean and standard deviations in which the number of people who earn each grade is determined by statistics. Why aren’t these courses graded on a curve? Some people believe that a “curve” means better grades for all or a more generous grading system. In fact, the opposite is true. Statistics define the arithmetic mean (i.e., average grade) and the standard deviation defines the distribution of scores relative to the mean. Slightly more than two-thirds of all grades (68.2%) are within one standard deviation of the mean, 34.1% above it and 34.1% below it. About 95% of all grades are within two standard deviations (43.7% each above and below). This is called the normal distribution or bell-shaped curve. Independent of the average on an exam, the average (mean) and standard deviation can be used to find your ranking. The disadvantage of the “curve” is that when students withdraw, the average scores change with the population. When students with the lower scores withdraw and are no longer counted, the “average” of the remaining students keeps increasing. With a grading “contract”, UGA students always have a sense of where they stand in an absolute sense. There is also more incentive to students because there is no limit to the number of each grade.
