Twelfth-grade student work intensity linked to later educational attainment and substance use: new longitudinal evidence

Bachman, Jerald G; O’Malley, Patrick M; Schulenberg, John E; Freedman-Doan, Peter C.; Staff, Jeremy. (2011). Twelfth-grade student work intensity linked to later educational attainment and substance use: new longitudinal evidence. Developmental psychology. 47(2), 344-363.