“Our aim was to determine the association between childhood academic ability and the onset and persistence of tobacco, alcohol and cannabis use across adolescence in a representative sample of English schools pupils.

High academic ability was also positively associated with occasional and persistent cannabis use in late adolescence.

In a sample of over 6000 young people in England, high childhood academic at age 11 is associated with a reduced risk of cigarette smoking but an increased risk of drinking alcohol regularly and cannabis use. These associations persist into early adulthood, providing evidence against the hypothesis that high academic ability is associated with temporary ‘experimentation’ with substance use.”

https://www.ncbi.nlm.nih.gov/pubmed/28228447