„Dozens of studies have demonstrated many differences in the way advantaged and disadvantaged parents engage their children and how these differences matter to children’s adult success. Among other things, advantaged parents spend more time, in particular on educational activities, with their children and produce more cognitively stimulating home learning environments. […] The gaps in parental time investment are important because research suggests that spending time with a child has a direct and causal effect on children’s cognitive test scores and that it is the most productive input for cognitive skill development.“
Univ.-Prof. Dr. Susan E. Mayer u. a., „Using behavioral insights to increase parental engagement“ (2015), S. 4f