Summary: GAO discussed students' and parents' knowledge of college costs, and federal and private-sector student aid programs. GAO noted that: (1) students and parents had limited knowledge of the cost of attending different kinds of schools, and the availability of student aid; (2) students and parents from low-income families knew more about grants, while those from higher-income families knew more about loans; (3) higher education institutions were the primary source of information about financial aid for most students and parents, followed by such informal sources as family members and friends; (4) high school counselors were not regarded as important sources of financial aid information; (5) families with knowledge of financial aid at the time their children were in high school were more likely to apply for aid than families without knowledge at that time; (6) private-sector college aid programs had limited data for evaluation of efforts; and (7) between 1988 and 1989, over 42,000 students were involved in private-sector programs involving early notice of guaranteed financial aid, but those programs differed greatly in their assumptions, designs, and costs.