This 10-year study compared the achievement of 3 samples of students designated at-risk for school failure and 1 sample deemed not at risk, and followed a transitional first-grade school readiness program (SRP) population from prekindergarten through eighth grade to identify contextual factors associated with student progress. At-risk samples were students in a transitional first grade (SRP); students recommended for the transitional program but not placed (SRP-NP); and students retained in kindergarten, first, or second grade (RET). A sample of promoted students (PRO) was designated as non-risk. A group of students held out (HO) for a year prior to kindergarten had unknown risk status. Data were collected through readiness tests, teacher ratings, parent surveys, standardized achievement tests, report cards, and other school records. Outcomes were contrasted for comparative analysis between samples. Results indicated that SRP students underachieved the PRO students on all salient measures from second grade onward. They did not perform better than the SRP-NP group on any achievement measure. SRP students rated as aggressive (close to 35 percent) had lower achievement than nonaggressive SRP students. SRP students were subsequently referred to and placed into special education by second grade more often than PRO students, SRP-NP students, and HO students, but at the same rate as RET students. The most significant early risk factors for poor achievement among SRP students were increased age and distinct aggressiveness. Successful SRP students had higher initial achievement test scores and mothers with higher levels of education than nonsuccessful SRP students. Initial kindergarten behavioral and parental factors were better predictors of second-grade achievement than readiness measures. Ratings of personal-social deficits in kindergarten predicted lower seventh-grade grade point averages. (Contains 131 references.) (KDFB)