Grade inflation. Whereas price inflation refers to the same amount of money having less purchasing power now than in the past, the idea of grade inflation seems to work in the opposite direction. The same quality of schoolwork (if that could be objectively verifed) is likely to have its grade-earning power get better over time. To use writing as an example, an essay whose reasoning, creativity, and writing might have warranted a B in the 1990s could well receive an A today.
We don't actually have cases of the same exact paper being submitted in different decades to see if it indeed gets better grades over time (unless students are cheating or researchers are running a devious experiment). Therefore, we have to look at more indirect evidence. One such source is a graph in this New York Times blog column on college grade inflation.
The graph shows that for most of the last 70 years, B's were the most common grades. However, starting in the mid-1990s, A's began to overtake B's. A's, which account for nearly 45% of all grades according to the most recent (2008) statistics, are now comfortably in the lead. C's, once comprising as much as 35% of grades, now are given to about 15% of students. D's are F's are rarely given anymore, each most recently accounting for about 5% of grades. (If my experience as a professor is any indication, I suspect that a lot of the D's and F's students receive today stem from failure to turn in assignments, not D/F grades on work that is turned in.)
In theory, of course, it could be that today's college students are just so much brighter than their predecessors that the high grades currently being awarded are totally justified. Neither the researchers whose work is cited in the Times nor, I suspect, most academicians would buy that proposition. There are contrarians, however. (It's beyond the scope of this column, but there is evidence that performance on IQ tests has been rising over the generations, a phenomenon known as the Flynn effect.)
The Times piece finds grade inflation more prevalent at private than at public colleges and universities. Grading is more stingy in the South than in other U.S. regions, and at science/engineering oriented schools. The website gradeinflation.com (yes, such a URL does exist) provides data on specific institutions and academic disciplines. This report from Minnesota State University discusses several possible reasons for grade inflation.
Some universities have imposed systems intended to counteract grade inflation. In 2004, Princeton imposed a limit of 35% on how many students could receive an A (this USA Today article notes that, "There is no quota in individual courses...," so the 35% appears to hold in the aggregate over courses and departments).
Professor Ian Ayres writes in his book Super Crunchers (about "number-crunching" statistical analyses) that when he taught at Stanford Law School, each class was required have a 3.2 mean for its grades. On a semi-facetious note, I've always wondered how this grading requirement is enforced. Perhaps non-compliant professors are made to teach 8:00 a.m. courses, stripped of their parking privileges, or made to dress up as the Stanford tree mascot!
(My thanks to David P. Schmitt, whose Facebook posting on grade inflation led me to some of the above sources.)