"According to new research published Thursday in the American Sociological Review. children whose parents divorce perform worse in math and have poorer social skills, and they struggle more with anxiety, loneliness, sadness, and poor self-esteem than their peers whose parents are not divorced. They are also more likely to have trouble making friends and maintaining those friendships, expressing emotions positively, and getting along with other kids who are different from them."
The study, also reported in USA Today, tracked children from kindergarten through 5th grade and focused on those whose parents divorced between 1st and 3rd grade. The USA Today story points out that problems did not show up in school before the divorce process began -- it was not the bad marriage, but the divorce itself and perhaps post-divorce developments, that correlated with the problems.