First of all, getting bullied lowers students self-esteem, makes them not want to attend school.
A high level of bullying was consistently associated with lower grades across the three years of middle school. The students who were rated the most-bullied performed substantially worse academically than their peers. Projecting the findings on grade-point average across all three years of middle school, a one-point increase on the four-point bullying scale was associated with a 1.5-point decrease in GPA for one academic subject (math) - a very large drop.
This article by Stuart Wolpert shows that students who get bullied have hard time to focus on their studies. They feel like they are in danger all the time but most importantly they become unhappy and even suicidal.
“According to statistics reported by ABC News, nearly 30 percent of students are either bullies or victims of bullying, and 160,000 kids stay home from school every day because of fear of bullying.”
Generally, students who bully others were also bullied by older students when they were younger, that is the reason they do not feel like it is a big issue; because they had been hazed, they think they have right to haze others. Hazing, mocking, teasing, bullying may become very serious after a while, it should be stopped immediately. Bully usually start with little things such as mocking, teasing if it is not stopped right away, it may get bigger. Once bullies realize that the younger kids are afraid of them, they feel more powerful and the more powerful they become the worse the hazing