Bell Curve: An Analysis of Grading on a Curve in Academics

Edited by Aurna Nidamarthy

Bloom and Blaze sat nervously in their room, frequently checking text messages on the phone. The CBSE Board Class 12 results were to be declared any moment. This would certainly be a defining moment in their life as they would know which university would accept them for an Admission Process. There was some uneasy excitement because they had studied very hard for their 12 grade exams. Blaze studied alone. He worked out a 12-hour regular schedule where he learned most of the books word by word. On the other hand, Bloom spent 4 hours a day with a peer group to discuss concepts and make notes during his preparation process. The results were finally declared, and Bloom aggregated 81% and Blaze scored a whopping 98.8%. Press cameras clicked on Blaze - a Superstar proclaimed by the press. A high performer was born by achieving a 100 in most subjects other than mathematics. Blaze walked into the best college in the country with the highest cut off.

Bloom sat at home in gloom as he tried to decode why some subjects had pulled down his aggregate. He began by understanding the concept of the Bell Curve and how most grades of students were pushed within this curve.


The "curve" being referred to is the"bell curve," which is used in statistics to show the distribution of any set of data. It's called a bell curve, because once the data is plotted on a graph, the line created usually forms the shape of a bell or hill. In case of a normal distribution, most of the data will be near the middle or the mean, with very few figures on the outside of the bell – the extreme outliers.


Curves help to analyze and adjust scoring if necessary. If, for example, if the Board decides to analyse scores and sees that the mean (average) grade of the exam was approximately a C (70%), and slightly fewer students earned Bs and Ds and even fewer students earned As and Fs, then it could be concluded that the test was a good design if they use a C (70%) as the average grade.

If, on the other hand, the Board/University plots the test grades and sees that the average grade was a 60%, with no grades above an 80% then they could conclude that the test may have been too difficult.


These are a few of the most popular ways that grades are put on the Bell Curve:

  • Add Points: A person correcting the examination sheets tops off each student's grade with the same number of points.

  • When It Can Be Used: After the exam, if the Board/University determines that most of the students got, say questions 5 and 9 incorrect, they may decide to add a point about the relative performance of the student and mark them based on that.

  • Benefits: Everyone gets a better grade.

  • Drawbacks: Students do not learn from the question unless the Board/University offers a revision.

  • Move a Grade to 100%: Board/ University as a policy decides to move the highest scoring student’s score to 100% and adds the same number of points to everyone else's score.

  • When It Can Be Used: If no one gets a 100%, and the closest score is an 88%, for example, a paper corrector could determine that the test was too tough. If so, he could add 12 percentage points to that kid's score to make it 100% and add 12 percentage points to everyone else's grade, too.

  • Benefits: Everyone gets a better score.

  • Drawbacks: The kids with the lowest grades benefit the least (a 22% plus 12 point is still a failing grade).

Bloom came to terms with this analysis and understood that his grades were pushed on a curve and were relative to the students who had appeared for the board exams. Furthermore, he understood the Pros and Cons of the Bell Curve.

Bell Curve Grading: it’s Pros and Cons.


· Allows for screening students according to their performance relative to their peers.

· Useful for competitive circumstances where students need feedback as to how they compare to their peers in content mastery.


· Does not provide feedback about the actual content mastered by the student.

· Curve arbitrary (and thus meaningless) unless tied to individual needs and goals.

· Discourages collaboration, as competition becomes central.

Sound Strategies

· Establish minimum achievement standards linked to content mastery and then calculate number of As, Bs, Cs, etc. based on the curve tied to student's performance relative to his/her peers.

· Establish department standard curve. Eg: Mathematics, Business Studies, Organisational Behaviour can have their own standard averages.

Why should we Do Away with the Bell Curve in Grading students?

Avoid a Zero-Sum Game.

Blaze has an edge over Bloom by scoring better. This grading system creates an atmosphere that’s toxic by pitting students against one another. At best, it creates a hypercompetitive culture, and at worst, it sends students the message that the world is a zero-sum game.

Encourage Collaboration within an Ecosystem

If Blaze and Bloom were to collaborate on their strengths in mastering the curriculum, pushing the grades on the curve would not have been required. Blaze would have scored 88% in most subjects and would have still had room for improvement. Studies say content mastery can best be evaluated if students are assessed individually, keeping in mind collaboration of projects within an ecosystem. An ecosystem where students help each other understand core concepts towards mastery of content.

Encourage Transactional Memory

Blaze may have been great at learning by rote. Education isn’t the knowledge you accumulate in your head. It’s the skills you gain about how to learn which improves Transactional Memory. This is developed through discussion and group projects.


The bell curve system reduces social cooperation and trust among students. It creates an unhealthy environment where many students are afraid to help one another because they are worried it will hurt their chances of getting an ‘A.’

The bell curve system is a waste of students’ time. In order to increase their chances of scoring a distinction, students would have to spend much more time and effort on their studies than they really need to. This time spent on trying to rise above the bell curve causes students to miss out on opportunities to build relevant skills to prepare for the working world.

I would strongly recommend Educational Boards/Universities to move on and dump the Bell Curve for the sake of having a developmental educational system closer to what the working world seeks - a world where relativity is passe and developing performers is vital.

“My major hobby is teasing people who take themselves and the quality of their knowledge too seriously and those who don’t have the guts to sometimes say: I don’t know...” - Nassim Nicholas Taleb


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