High school sophomores' (N=1,717) self-reported coursework and grade information for 26 courses was collected as part of a fall 1991 Preliminary American College Test Plus (P-ACT+) administration. Students were from 55 high schools. The accuracy with which students reported courses taken and grades earned was investigated by comparing this information to data obtained from school transcripts. The typical (median) proportion of students providing accurate reports of courses taken was 0.96. The typical proportion of students accurately reporting grades was 0.64, and the corresponding median correlation between self-reported and transcript grades was 0.79. Variation in reporting accuracy was found across schools and for selected subgroups of students. Students' self-reported coursework and grade information appeared sufficiently accurate to be used for research concerning the educational development of groups of students. Self-reported grades did not appear to be sufficiently accurate for use in decisions concerning the educational development of individual students. Two appendices contain forms used in the study, and eight tables present study information. There is an eight-item list of references. (Author/SLD)