For high school students, working more than 20 hours a week at a part-time job could be doing more harm than good, a new study suggests.

The study, authored by researchers at the University of Washington, the University of Virginia and Temple University, found that working more than 20 hours a week in high school is associated with decreased school engagement and increases in problem behavior. The study is published in the January/February issue of the journal Child Development.

These results contradict a number of recent studies that found no negative effects on students from working intensive hours, but researchers say that the treatment of their data, using advanced statistical measures, may account for this difference.

According to the study, students who worked more than 20 hours a week had lower expectations for educational attainment, lower school engagement, higher levels of substance abuse, and other problem behavior. However, these same students also showed more autonomous decision-making and had slightly higher grade point averages than teens without jobs.

The researchers believe that students working long hours tend to take easier classes, which may account for the GPA increase and less time spent on homework.

The authors say they found virtually no evidence that working fewer than 20 hours a week has negative effects on students.

Source: USA Today
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