Promoting academic achievement: the role of peers and family in the academic engagement of african american adolescents
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The findings from hierarchical linear regression indicate that socializing with peers who engage in risky behaviors has a significant, negative impact on academic engagement. Family cohesion also was significantly associated with academic engagement over and beyond the effects of risky peers.
So don't let your kids hang around with drug users, stay married, be loving towards your kids and they'll do better at school.
WOW! Breakthrough social theory.
Sorry for the sarcasm. It's just obvious, why is this not talked about or implemented?