According to a study from University of Tübingen involving students from academic track schools in Germany, students who performed best and achieved the highest scores were those whose families enjoyed math and believed they were good at it ("motivated" parents), even if these parents were not involved in helping their children ("disengaged" parents).
Originally Posted by study
"A favorable pattern of students' academic outcomes was found when families were interested in math and perceived their own math competence to be high, regardless of their amount of academic involvement,"

Originally Posted by Abstract
Students from families classified as motivated and disengaged showed higher initial levels motivation and achievement. Over 5 months, these students also showed an increase in self-concept and higher achievement than students from other family types.
According to this study, direct parental involvement is not necessarily the key to enhancing a child's academic achievement; Role-modeling an interest in math along with a strength in math may have a stronger positive influence.

Possibly these higher achievers with disengaged parents are developing an internal locus of control, or sense of owning their education.