The recent rapid increase in divorce, along with its distinctive cultural and welfare environments for single-parent families, makes Korea an interesting case for examining effects of single parenthood on children’s education. Using data from Korean 9th and 12th graders, I compare the levels of educational aspiration and student disengagement between students with two parents and those with a single parent, distinguishing divorced single fathers, widowed single fathers, divorced single mothers, and widowed single mothers. Logistic regression analyses show that students with a divorced single parent, regardless of gender of the parent, are much less likely to aspire to four-year university education and more likely to be disengaged than their counterparts with two parents. The effects of widowhood disappear once control variables are held constant. Lower household income among single-parent families explains in part the poorer educational outcomes of their children. Parent-child interaction is another important mediating factor for the effect of single fatherhood but not for single motherhood. The relevance of the extended family system and distinctive features of post-divorce living arrangements in Korea is discussed to understand the effects of single parenthood.