An ongoing study was initiated to provide a reliable means of defining and measuring factors affecting students' performance as they move from high school to college, including the reasons why some are more able than others to excel and/or persist. The study provides public high schools, colleges, universities and the Missouri Coordinating Board for Higher Education with high school characteristics information and college data for nearly 15,000 entering college freshmen. The data includes American College Testing Service (ACT) scores, high school and college grade point averages, major, nearly all of the high school characteristics shown to be related to college success, credit hours earned, and other data on student interests and demographics. In the first year of the study, the data consisted of ACT test scores, college or university, grade point averages, credit hours and stated majors. The first-year statistical analyses and reports sent to the participating institutions are described and illustrated, and a summary of the first-year results is provided. One of the primary first-year results was the finding that only 23.5% of the students had completed the core curriculum; when the foreign language requirement was excluded from consideration, this figure was 45.3%. The second-year methodology and some preliminary results are also discussed, and an overview is given of the methodological problems and considerations. The study is considered to be valuable for state coordination and policymaking, to the institutions involved, and as a bridge for communication among the players. Four selected reports of the data are appended. Contains 5 references. (KM)