Dan Koretz and Mark Berends, RAND, 2001
The RAND Corporation's Dan Koretz and Mark Berends went hunting for evidence of grade inflation in U.S. high schools during the decade 1982-92. (They were only able to get data for math courses.) They found no nationwide grade inflation, but they did find some among high-income students and in urban schools. They also found general improvement in students' math proficiency. This 80-page report gets pretty technical and jargony ("after disattenuating for unreliability....") but you may want to have a look. You can find ordering information or download a (PDF) copy by surfing to http://www.rand.org/publications/MR/MR1445/.
