Classroom teachers do not always follow recommended grading practices. Why not? It is possible to conceptualize this question as a validity issue and ask whether teachers' concerns over the many uses of grades outweigh concerns about the interpretation of grades. The purpose of this study was to investigate the meaning classroom teachers associate with grades, the value judgments they make when considering grades, and whether the meaning or values associated with grades differed by whether teachers had measurement instruction. A sample of 84 teachers, 40 with and 44 without measurement instruction, responded to classroom grading scenarios in two ways–with multiple-choice responses indicating what they would do and with written responses to the question, “Why did you make this choice?” A coding scheme based on Messick's (1989a, 1989b) progressive matrix of facets of validity was used for quantitative and qualitative analyses of written responses. The meaning of grades is closely related to the idea of student work; grades are pay students earn for activities they perform. The relationship of this notion to classroom management should be investigated. Teachers do make value judgments when assigning grades and are especially concerned about being fair. Teachers also are concerned about the consequences of grade use, especially for developing student self-esteem and good attitudes toward future school work. Measurement instruction made very little difference, although it did reduce the amount of self-referenced grading reported.