Why do we use red in grading? The scientific and psychological reasons and effects of red grading

The color red is conspicuous and warning, but it can also be warm and encouraging. When grading, use green or blue to reduce the negative effects of incorrect answers and red to maximize the positive effects of correct answers.

 

Some elementary school students have a “red pen” study guide. There are also home visits from tutors called “red pen teachers” to help students. As a child, I had a red colored pencil as a staple of my Kumon learning teachers. You may remember taking a test in elementary school and receiving a test sheet with a red score and a “good job” written on it. The red colored pencil, which is a piece of paper rolled around a colored pencil lead, has been used by teachers since elementary school. But why red? Why does “grading” typically conjure up images of red circles and crosses on white test papers? Of course, there are many other colors that are used for grading, depending on personal preference, but it’s worth noting that red is the color that comes to mind when we hear the word ‘grading’.
When you look at it scientifically, there’s some support for the idea that it’s because red is so visible. Red is one of the primary colors with a wavelength between 620 and 740 nm. The most common representation of red has a lightness of 4 and a saturation of 14, making it the most saturated color along with yellow. Commonly used test papers are gray with a lightness of 7 to 9 and a saturation of 0, and writing is black with a lightness of 0.5. High visibility means that it has a large difference in brightness and saturation from the surrounding color, and in the case of red, the difference from the surrounding color, the color of the test paper, is large compared to other colors, so it stands out clearly. However, in reality, there is not much difference between a saturation of 14 and 10 compared to gray, which has a saturation of 0. In other words, there is no noticeable difference between red and green, blue, and purple, which have similarly low brightness. If you don’t have a lot of black text, you might actually find that purple, which has a lower lightness of 3, is more noticeable. In other words, it’s not just that red is more noticeable.
If we look at the general perception of the effect of red, we find that people associate it with warning, danger, and prohibition. Because it’s the color of blood, it’s also associated with aggression and threats. So, you might think that by grading in red, you’re highlighting what’s wrong and sending a message of warning to pay attention and get it right. In fact, some studies have shown that grading in red makes students feel more intimidated and harshly judged. Some schools in English-speaking countries have even banned red pen grading. So, is the only reason to grade in red really just to make incorrect work stand out more and serve as a warning?
While the color red has some negative connotations, it also has positive ones, such as loyalty and warmth. For example, Orion’s chocolate pie, Jung, was previously packaged in blue, but the company switched to red because it felt that red was a more appropriate color for the product’s “Jung” symbol. The color red is also associated with passion, confidence, joy, and cheerfulness. Just look at the red T-shirts worn by the entire country during the 2002 Korea-Japan World Cup. In addition, the Chinese prefer the color red because they believe it wards off bad energy.
In this sense, when teachers use red to grade papers, it shows their warm love and affection for their students. Grading with a warm red color, rather than a cold blue color, shows the teacher’s desire to encourage students to work harder with confidence and enthusiasm, not to get frustrated when they get circled or wrong. If it’s graded in green, which is a calm and serene color, does that in itself make students feel supported by the teacher? A red pen teacher is more plausible than a blue pen teacher because it implies encouragement and energetic energy.
Why not use other ways to maximize the effect of the color red, which can give such good energy? While there are positive aspects to the effect of red, there is no denying that there are also negative aspects. No matter how encouraging and praising you use the color red, if students perceive it as a warning, it won’t have the positive effect you want. If you use red for more crosses than circles, or if you use red for critical comments, the student will feel more warned and harsh. So I would suggest changing the way you use red: use a larger circle, like a sun, to make it stand out more, and use green or blue, which are less warning colors, for the parts you want to point out that are wrong or incorrect. The red circles are meant to build confidence and enthusiasm for the correct answers, and the complementary green and blue circles are meant to highlight the wrong answers to some extent. Isn’t this a win-win situation, where the student is not hurt and the teacher is encouraged?