 # How to Grade on a Curve & Why Is It Needed?

Sometimes, knowing how to grade on a curve can come in handy if you are a student. It may happen that the student performed worse than expected on a test. In some cases, teachers can use various methods to adjust the student scores to equalize them. In this article, we will reveal the whole picture of grading on a curve so you can understand all aspects and features of it. So let’s cut to the chase!

## What is Grading on a Curve: Definition & Example

In this paragraph, let's discuss what is grading on a curve, its importance, and its main aspects. It may sometimes happen that a teacher needs to curve the grades by assigning scores to different academic tasks based on the performance of the whole class. Why is that needed? And what are the main features of grading curves? Everything is easy - when curving grades, a professor can clearly see the general class performance and understand whether the test was of the appropriate difficulty. The curving method allows a student to recoup some points they lost on a particular assignment. Mainly, grading on a curve increases the students' grades by moving their actual scores up a few notches.

Let’s look at the example:

After the test, the highest percentage grade in the class was 85%. So 15% is the difference. Hence, the teacher can choose to add these 15 percentage points to each student's test score.

In other words, if the test is about 70 points and the highest score is 68 points, the difference is 2 points. The teacher can add 2 points to each student's test score.

## What is the Purpose of Curve Grading?

Before you do any curving, you have to determine what you want to get from it. The purpose of the grading curve is to fix the academic performance or increase the students’ average score. Apart from it, this approach can also help teachers adjust their materials. Here are some of the points grading curve can help to fix:

• Provide the possibility to re-do assignments/ tests;
• Exclude excessively complex tasks from the program;
• Assign easy-scoring tasks to your students if they fail with a complicated test.

Regardless of the way you follow, it is always important to keep an eye on the fairness of the average grade since it may sometimes need some fixing from both the student and the teacher. The best approach would be to adjust your strategy to a particular case.

## Why Do Teachers Use a Curve?

Teachers use the curve to analyze their tests. Bell curve grading can help them suggest if the material they present is good. For example, if the teacher sees that the average grade was low, then the test may have been too difficult or hard to understand. In contrast, if the class score has a wide range of different grades (most of the students got C, less students got Bs and Ds, and even fewer got As), then we can assume that the test was good.

A normal distribution of grades on a bell curve in the class of 35 students will look like this:

One student would get an A (2% of the class)
Seven students would get a B (14%)
Nineteen students would get a C (68%)
Seven students would get a D (14%)
One student would get an F (2%)

If the teacher sees such a picture, then we can suggest that the text is well-designed.

## How to Curve Grades: 4 Methods

There are multiple ways to curve grades. Now let’s look at the top 4 methods of how to curve grades.

### Method 1: Mathematical Curving Approach

This is one of the most widely used grade curving methods, being very easy to follow. Start with assigning 100% to the highest score you have. The value of other grades is calculated based on the “100% top level” you have just identified on the curve. As a result, all the scores will be higher since the pre-set 100% excellent score is different from how it was initially. If done correctly, the method will boost your scores greatly.

For example, you have 90% out of 100% for the Biology test. The calculation should go as follows: 100 - 90 = 10, which means you need to add 10 to each and every grade of yours. Thus, you will adjust all your scores to the hypothetical “perfect” score.

Another good thing about this method is associated with its flexibility. You can apply this formula to absolute values. The logic of calculations remains the same.

### Method 2: Use a Flat-Scale Formula for Curving Grades

It is another easy and fast method to grade curve, which is especially useful in cases where there was one difficult assignment and many students have failed to complete it correctly. Grading on a curve formula is very similar to the first one and is based on adding a pre-set value to all the scores, although you do not have to set up 100% for the highest grade. It is you who decides on the value to add.

You can add 10 or 5 to all figures; thus, there might be no 100% in the point range. At the same time, there is also a possibility of scores that exceed 100%. That’s why it is so important to decide on the benchmark.

### Method 3: Use a Bottom Limit to Define an F

If you have a question about how much will a test lower my grade, here is good news. It may happen that a student has failed a test, scoring 0 even though his academic performance has always been satisfactory. As a result of this academic assignment, he might get a failing value, which is unfair. To prevent this situation from happening, many teachers set a bottom limit for any failing value that is higher than 0 points. Thus, the increase the final value.

For example, a student fails the test and gets an F. Consequently, his final grade is less than 50, which is a failing score. Fortunately, it is still possible to make his average score higher. To do this, it is only necessary to set a lower limit on failing scores, for example, 40%. As a result, the new GPA of a student will be 63,3%, which is not F anymore.

### Method 4: Use a Bell Curve

Let’s look at another method of how you can be graded on a curve. This method implies that you find the average value and adjust all other (higher/ lower) points. Let’s assume the average point is 66%, which you set up as a C. Thus, to separate low from high grades, you just need to either add or deduct a particular amount of points; you can decide on this amount yourself. Let’s say you decide to use 12 for this purpose.

As a result, you get 66 + 12 = 78, which is a B; and 66 - 12 = 54, which is a D.
As a result, you objectively raise the score level gradually without going extreme.

So, summing it up, the main advantage of the curving grades is that it fights grade inflation: if a teacher doesn't grade on a curve and, for example, 40% of her class could get an "A," which means that the "A" doesn't mean very much. An "A" grade should mean "excellent". But theoretically, 40% of any given group of students are not "excellent." So grade curving will help teachers avoid such situations by adjusting grading curves of their tests.

If you feel you have some issues with your grades, you can simply contact our academic service to get any kind of help, from doing your homework to helping you with your essay.

Rachel R. Hill is a real educational devotee. She prides in writing exceptional general guides while listening to every need of students.

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