One of the most alarming social trends in the past 40 years is the increasing educational disadvantage of children raised in low-income families. Differences between low- and high-income children in reading and math achievement are much larger now than they were several decades ago, as are differences in college graduation rates. What might account for these increasing achievement and attainment gaps? One obvious suspect is income inequality itself, which has increased dramatically during the same period. But income inequality is hardly the only factor that may be widening the gaps. This article focuses on the central concern of the Moynihan Report: the rise of single-parent families, which has been much more rapid among those with low incomes than among those with high incomes, and indeed has fueled some of the increasing income inequality. The Moynihan Report focused on black families, but the rise in single-parent families transcends racial and ethnic boundaries. In the analysis presented in this article, the authors examine the relationships between children's completed schooling and a number of factors, including single-parent family structure. They find that, while statistically significant, the strength of the relationship between living with a single-parent family and educational attainment is comparable to the relationships for family size and the age of the mother at the time of the child's birth and weaker than the relationship for maternal schooling. It is troubling, however, that the negative relationship between living with a single parent and educational attainment has increased markedly since the time the Moynihan Report was published. In other words, American children raised in single-parent homes appear to be at a greater disadvantage educationally than ever before.