Using data from the Early Childhood Longitudinal Study, this study employed a latent growth curve model to examine how parental involvement explains the association between maternal employment status and children's math and reading achievement growth from kindergarten through the third grade. To address this issue, three types of parental involvement--school participation, parent-child interaction, and educational trips--were considered. Our findings indicated that maternal employment can be both beneficial and detrimental to children's educational development depending on the mother's number of working hours. Students whose mothers were employed part time exhibited an advantage in academic learning because of increased rates of school participation and parent-child interaction, whereas students of mothers employed full time appeared to experience a lower learning growth, given lower rate of school participation and fewer educational trips than students of unemployed mothers. These findings highlight the importance of family context in understanding work-family relationships. (Contains 3 tables and 2 figures.)