End-of-the-semester teacher evaluations are short, simple questionnaires, but they have the power to make or break a teacher’s career.

Although the evaluations may seem like afterthoughts at the end of class, they have a huge effect behind the scenes. Instructions on evaluations say that the University of Minnesota may use the information to determine the salaries, promotions and tenure of faculty.

In responsible hands, evaluations reward good professors and help improve bad ones. At other times, however, evaluations become tools with which to punish unpopular professors.

Few things upset students more than receiving low grades on a test or an important assignment. It can be especially frustrating when a student feels they’re struggling to succeed because their professor isn’t teaching course material clearly. I doubt there’s a student at the University who hasn’t once blamed their teacher for a bad grade because they wrote a confusing test question or tried “tricking” students on a test.

There are times when the grade may actually be unfair, but there are plenty more when it’s wholly deserved — it’s just the result of the class’s grading curve or difficulty.

But a University of Minnesota professor has received negative evaluations for nothing more than being a tough grader. Students’ reasoning is easy enough to understand: If you dislike the grade, then punish the professor who gave it.

While the reason may be simple, the consequences are vast. In the long term, it’s a dangerous practice to punish teachers for a curve or simply a bad grade.

At the University, the Carlson School of Management froze a professor’s salary and required him to take a teaching seminar because he received too many negative reviews regarding his grading policy.

Such professors face two choices: pacify the students who wrote negative reviews or risk punishment — perhaps even unemployment. Which do you think is more common?

Unfortunately, it’s all too easy to blackmail — or least pressure — professors into giving good grades. Students hold influence over their teachers’ reputations, careers and abilities to survive in academia.

But when does the coercive power stop?

Obviously, not everyone can get A’s, despite what students might want. However, enough student protest could raise the number of A’s high enough to diminish the grade’s value. This dilution, or grade inflation, plagues universities across the country.

For example, The Harvard Crimson, Harvard University’s student newspaper, recently revealed the median grade at that school an A-minus. The most common grade is an A. Yale University and Princeton University had to recently address similar problems.

Of course, while grade inflation may sound great to students looking to maintain a healthy GPA, it may diminish the credibility of a university’s graduates.

When everyone is “above average,” it becomes difficult for graduate schools and employers to discern who is actually worth admitting or hiring. Obviously, schools won’t accept everyone. Instead, they will seek out graduates from a more reputable establishment.

Grade inflation is rooted in many sources, not just teacher evaluations, but we need to complete evaluations responsibly if we want to avoid exacerbating inflation.

Although teachers typically distribute evaluations at the end of class, students shouldn’t scramble to complete them. They exert a profound influence on teachers’ professional and personal lives.

If a student is thinking of giving their teacher a negative review merely because of a bad grade, I urge them to consider exactly why they received the grade in the first place.

Before looking at the grading curve, think about a professor’s teaching skills, helpfulness and accessibility. These are the things that truly make a teacher unique, and they are the things worth evaluating.

The best professors often teach the hardest classes, where it’s certain that some students will succeed while others struggle. Using evaluations as a way to punish a professor will harm the education system — and students — in the long run.

In short, college isn’t high school, and the professors aren’t there to coddle you. There is an unspoken contract between teacher and student, one that demands effort from both sides. If either lapses, then learning will suffer.

We must remember that the purpose of teacher evaluations is to remedy lapses on the professor’s side, not on the student’s side.