“…There are two exceptions to the general conclusion that less is better when it comes to student work intensity: First, those working zero hours report poorer outcomes than those at low or moderate levels of paid work; and second, among those who did hold paid employment in 12 th grade, longitudinal analyses show little distinction in long-term educational attainment whether they had worked 1–5, 6–10, or 11–15 hours (Bachman et al, 2011). Another key finding from MTF and most other research is that although adolescent work intensity during the school year is correlated with negative outcomes, at least a good deal of the association seems attributable to prior more fundamental differences, i.e., selection effects (Apel et al, 2007; Bachman, Safron, Sy, & Schulenberg, 2003; Paternoster, Bushway, Brame, & Apel, 2003; Mortimer, 2003; Rothstein, 2007; Schoenhals, Tienda, & Schneider, 1998; Staff, Osgood, Schulenberg, Bachman, & Messersmith, 2010; Staff, Schulenberg, & Bachman, 2010; Warren, 2002; Warren, LePore, & Mare, 2000). Nevertheless, there is also evidence suggesting that high work intensity has negative impacts on educational attainment and may also contribute to long-term cigarette smoking (e.g., Bachman et al, 2011).…”