This paper describes the effect of teacher comments, students' demographic information and learning management system utilisation on student final scores in algebra courses in a K-12 virtual learning environment. Students taking algebra courses in a state virtual school in the Midwestern US region during 2007-2008 participated in this study. Student final scores on these courses were collected using tests administered at the end of semester in the virtual school courses. The hierarchical linear modelling technique was used for data analysis to account for the influence of school characteristics on student final scores. The results show these factors have different influences on student final scores in different algebra courses. The discussion of the findings addresses the implications for teaching. (Contains 4 tables.)