Educators are increasingly recognising the importance of improving students' mathematics achievement. Much of the current research focuses on the impact of instructional variables on mathematics achievement. The goal of this study was to examine the influence of less researched variables--family and student factors. Participants were 747 economically disadvantaged elementary students grades K-8 in Ohio. Predictor variables included: (a) 13 factors from a parent survey on both child and family circumstances and (b) reading achievement, measured by a norm-referenced achievement test. Outcome variables included three mathematics scales from the same achievement test. Regression analyses examined the impact of the predictors on the outcomes. Reading achievement significantly predicted mathematics achievement for all three outcomes. Parent pessimism and parent-perceived school/cognitive competence of children also emerged as significant predictors for two of the three mathematics outcomes. Implications for research, policy and practice will be shared.