Children are obviously affected by the way their parents nurture them. But to what degree? And who else is affected outside the family? The Harvard Family Research Project provides the beginning of an answer:
The results of the meta-analysis indicate that parental involvement is associated with higher student achievement outcomes. These findings emerged consistently whether the outcome measures were grades, standardized test scores, or a variety of other measures, including teacher ratings. This trend holds not only for parental involvement overall but for most components of parental involvement that were examined in the meta-analysis. Moreover, the pattern holds not only for the overall student population but for minority students as well.
Parenting affects a child's educational opportunities any way you cut the data. But by how much? The Journal of Child Psychology and Psychiatry published the following:
It is concluded that environmental effects on IQ are relatively modest within the normal range of environments, but that the effects of markedly disadvantageous circumstances are very substantial. (emphasis mine)
Parenting affects child development so profoundly that the lack of a loving nurturing environment has a "very substantial" impact on IQ, to say nothing of social and emotional development. Since children almost invariable end up in school together, parenting has a profound social impact on education and civil society. Indeed, parenting is the very foundation of a just society.
