Raise the Dropout Age or Let Them Go?
This paper uses these recent changes [in the school leaving age] in order to estimate the effects of further compulsory schooling. The results suggest that more restrictive laws reduced dropout rates, increased college enrollment, and improved career outcomes. Some caution is warranted, since focusing on recent law changes leads to higher imprecision. However, generally, the consistent findings in previous studies suggest that compulsory high school at later ages can benefit disadvantaged youth.
How large of a wage bump do students receive for staying in school for an additional year?
If we convert estimated annual earnings gains into lifetime gains, we see that a year of compulsory schooling increased lifetime wealth by an average of about 10 percent, including the revenue lost as a result of not working during school.
Increasing the school leaving age also decreases the dropout rate and increases post-secondary attendance:
States that increased the school leaving age above 16 witnessed an increase in average years of schooling for 20-29 year-olds by approximately 0.13 years, while high school dropout rates fell by about 1.4 percentage points. Raising the age limit also increased post-secondary school attendance by about 1.5 percent, even though postsecondary school is not compulsory.
The Oreopoulos chapter provides a nice overview of other studies on school leaving. My take: We need to create options for older students who've decided to return to school, but they should supplement, rather than supplant, the existing school leaving guidelines. I'm wary of setting 14 year-olds who would have stayed in school otherwise loose with the hope of ever recovering them. And the inequality implications of doing so are tremendous. Poor kids would be most likely to leave earlier and least likely to come back. While I acknowledge the potential benefits to the kids who stay (see Robert's post), I am more concerned about the likely damage done to the early dropouts.