Grading on the curve is a method of grading that is based on letter grades that are distributed on a bell curve. Typically, for an assignment or test, the average score becomes an average grade. The scores above and below the average are distributed accordingly.
This way of grading seems harmless, however, it can create imbalanced competition and learning outcomes, as well as inadequate learning achievements.
Grading on a curve was traditionally known to foster competition. Teachers who grade on a curve often create mixed emotions for a student to receive an A. The pressure of being one of the few to get a high grade is believed to stimulate students to work harder, study longer and take their class more seriously, but often the opposites happens.
Creating competition for a limited number of high grades can be more hurtful than motivational. Students want to develop a sense of self-worth instead of discouragement with their academic success.
If students can successfully compete for high grades, then opportunities for self-worth are created in the academic setting. Students who are discouraged by the lack of opportunities to get a top grade do not try hard.
In a classroom with scarce rewards, the inevitable result will be students that try hard but are not rewarded. This threatens self-worth and reduces motivation to work harder. The lack of motivation trickles down to the lack of appreciation for the subject matter, which is essentially the most important aspect of learning..
Creating a limitation also fosters self-loathing. Students are more apt to strive for success if they believe it is attainable. No one wants to continue if they do not believe they are of value. Assignments and grades should not be heavily focused on pass or fail. Rather, they should be based more on if the student understood the core concepts.
There are also potential anxiety issues over the curve grading system. Students who earn a B could end up with a C. This is another motivation killer that makes students feel like they have less control over how they are doing in the class.
For professors, the curve system makes it difficult to compare students and gauge comprehension of the subject material. If all the students are performing poorly, even the highest scoring student may be failing to meet the class standards.