Why do students at Yale focus so much time and effort on extracurriculars while often arriving unprepared for class? That’s just the Yale culture, or so I often hear. After all, when you get here, you’re immediately bombarded by the freshman bazaar. There are so many exciting activities, and your roommate just signed up for three a cappella groups, two club sports and a theater production, so you do, too.

This logic isn’t complete bunk, but I think there are more concrete explanations for why Yale’s culture encourages us to stretch ourselves thin, whereas places like the University of Chicago encourage studyaholics.

No one factor created this culture, but I think the root of the phenomenon is grade inflation. Before I explain this claim, first we need to dispel some myths about grade inflation and observe where the inflation actually takes place.

Some people say grade inflation has devalued the A. In fact A’s are still very difficult to get; it is the B’s that have become much easier.

Readily available statistics confirm how challenging obtaining A’s still is. Every year the top 5 percent graduate summa cum laude, the next 10 percent graduate magna cum laude and the next 15 percent graduate cum laude. Last year the GPA cutoffs for these distinctions were 3.93, 3.85 and 3.76, respectively. This means that around 1/3 of the student body receives the equivalent of about straight A-’s, about 1/6 get half A-’s and half A’s, and about 1/20th gets nearly straight A’s.

Of course many people do get A-’s, but these results show that only a minority can consistently get them. Furthermore, getting mostly A’s is clearly a real challenge. It’s nonsense to say that the A is meaningless when so few Yale students — most of whom probably received near-perfect grades in high school — can consistently obtain A marks.

The real grade inflation occurs on the lower end of the curve. According to Yale’s Office of Institutional Research, 80 percent of grades in 2006 were either A’s or B’s. Furthermore, according to a Yale Daily News poll from 2006, the average (self-reported) GPA is between 3.6 and 3.7. By comparing this average to the 30th percentile cutoff for cum laude in 2006 (which was 3.72), we see that the grade distribution is probably very tight. Though Yale doesn’t publish grade distributions, most informed Yalies would guess that the distribution is even tighter on the down side than the up side.

Of course, News polls are not scientific, but this evidence just confirms common knowledge: Especially in humanities courses, grades rarely fall below B’s.

Economists use the idea of elasticity to measure how much a change in one variable influences change in another. Applying this idea to grades, we can ask: To what extent does an increase in effort result in an increase in grades? The fact is that grades are very inelastic. B’s are relatively easy, whereas A’s are very difficult. Huge increases in effort effect only small increases in grades.

Because great efforts garner only small rewards, students are not encouraged to pour work into their classes. Instead, they can receive higher payoffs for their efforts doing other activities. Becoming the leader of a group takes a lot of work, but also looks great on a resume. In a trade-off between leadership and a letter grade increase, the leadership is probably the better choice.

On the other hand, imagine C’s were typical. I think few people would risk consistently skipping lectures and skimming readings. Because grades rarely drop below B’s, there are minimal consequences for skimping on work.

Even though grade inflation probably diminishes class participation and classroom learning, it is not necessarily harmful. We have to judge for ourselves whether we approve of this environment.

From my perspective, this sort of grade inflation actually enables us. One can distinguish oneself by studying hard to obtain top marks, or by taking on a truckload of extracurriculars. Both can be rewarding. Yale’s grade inflation doesn’t devalue hard work in class, but also encourages hard work in other passions.

College shouldn’t just be about learning to write papers. It should also teach students how to work with others; develop skills, such as playing instruments or sports; do research in labs or libraries; lead student groups and help the community. College is the launching ground for students to become adults. As such, it should encourage us to pursue activities that will enable us to function as adults. That means not just accumulating knowledge but integrating a life of the mind into real experience.

Tyler Ibbotson-Sindelar is a senior in Branford

College.