David Eggebeen is Associate Professor of Human Development in the Department of Human Development and Family Studies at Pennsylvania State University. His research focuses on aspects of the family. His interview with Mercator Net talks about how kids need fathers and how fathers make unique contributions to the welfare of their children. He also notes the separation between the rich and the poor over the issue of fatherlessness.
My own research shows that fathers uniquely influence their adolescent children. If the father has a poor relationship with his child at this age and does few activities with them, and if he has a low education level as well, it is more likely that both male and female adolescents will show signs of depression — regardless of what the mother is like. There is a similar effect with regard to teenage delinquency.
Regarding The class divide:
right alongside these (very involved) middleclass men are those who father children out of wedlock or divorce the mother of the child and literally abandon their children. So you have two groups of fathers out there — men who are investing heavily in their children’s lives, and men who are not feeling any responsibility towards kids.