Divorce can be very good for (some) children. A Spanish colleague was discussing the effects of the 2004 changes in Spanish divorce law — which require only a six-month waiting period in uncontested cases and no separation of living arrangements before the divorce becomes final.
In many Spanish cities there is substantial excess demand for places in some public elementary schools. Entry into the schools is on a first-come, first-served basis, but some preference for those places has been given to children of divorced parents.
Apparently parents have caught on to the incentives involved: Some parents are filing for divorce in January and February (the legal costs of a divorce are very low), with the divorce becoming final in the summer, so that their kids then acquire top priority for entry into a desirable elementary school. The parents re-marry shortly after the child is safely in a desirable school in September; and once in a school a child has the right to remain there.
It took several years for parents to realize the nature of these incentives, but even with complex incentives like these, parents can eventually take advantage of them to their own benefit.