Grade inflation in college is not a new phenomenon, but some of America's best schools are raising grades to new heights. While some college administrators are attempting to tackle the problem head-on, professors just are not cooperating.

• According to an internal report, the F still exists at Princeton, but only technically -- while Cs are becoming less common than grades of B or even A.

• Several years ago, Stanford brought back the F after a 20-year absence and called it a "not pass" -- but As and Bs still account for about 80 percent of the grades there.

• Professors at Columbia and Dartmouth still give most students As and Bs, although those schools report the number of As and enrollment in each class on students' transcripts to put the grades in context.

• A 1994 study of a representative sample of grades at four-year colleges nationwide showed A- had risen from 7 percent of all grades in 1969 to 26 percent by the end of 1994 -- and C grades or lower had dropped from 25 percent to 9 percent.

The Princeton report, which covered undergraduate grades over a 24-year period, showed 83 percent of the grades given between 1992 and 1997 fell between A+ and B-, compared with 69 percent between 1973 and 1977. Over the same periods, C+s fell from 5.8 percent to 3.7 percent, and Cs dropped from 6.1 percent to 3.6 percent.

Academics trace the escalation in grades to the Vietnam War -- when students with bad grades could be drafted and professors opposed to the war obliged by handing out high grades. Some professors today say they don't want to "penalize" their students by giving them low or mediocre grades. Many students contend they deserve high marks because they are smarter than their predecessors.