A longitudinal study of full- and part-time credit students was conducted at William Rainey Harper College (WRHC), Palatine, Ill., to provide comparative information on student performance and achievement between 1967 and 1981. A random sample of 200 full-time and 200 part-time students entering WRHC each fall during this period was selected, and the students' transcripts were examined to obtain data on grade point average (GPA), cumulative hours attempted and passed, persistence/attendance patterns, and number of semesters registering. The study revealed: (1) student GPA's rose following administrative decisions made in 1972 and 1974 which liberalized grading policies; (2) the average full-time student starting between 1972 and 1978 accumulated 42 credit hours and attended 4.4 semesters, and 35.5% of these students received a degree or certificate; (3) the average part-time student starting between 1971 and 1977 accumulated 17 credit hours and attended more than 3 semesters, and 11% of these students received a degree or certificate; (4) the percentage of full-time students taking continuing education courses rose from 8.0% in 1969 to 19.5% in 1974, then fell to 7.0% in 1980 and 1981; (5) the percentage of part-time students taking continuing education courses rose from 16.5% in 1967 to 29.5% in 1975 before falling to 13.5% in 1980 and 17.0% in 1981; and (6) the average student age throughout the period was 18.6 years for full-time students and 26 years for part-time students. (Author/HB)