Boys are generally far more likely to join gangs, use and abuse drugs/alcohol, and have disciplinary issues in high school. They also have more trouble forgoing short term pleasure for long term rewards in general. Our school, in seeking to prevent this by educating us about the problem, has offered what seems to be the prevailing explanation, and I’ll try to summarize it briefly here. I’m no neuroscientist, so don’t take any of this as gospel truth.
The short version: Teenage boys are naturally bad at impulse control for biological reasons. This means they tend to make poor decisions (like dropping out of school) or engage in the above behaviors (which often lead to dropping out).
The longer version: The prefrontal cortex (the part of the brain that deals with impulse control) generally develops fully only at the end of puberty. Until that happens, the most active part of a teenager’s brain is the area (which has a name I can’t recall) that responds to pleasurable stimuli - like the sex, drugs, and rock ‘n’ roll that more mature folks have been complaining about since time immemorial. That part of the brain is also known as the ‘reptilian brain,’ and the name is apt - when it’s dominant, teenagers’ ability to control their impulses and favor long-term gain over short-term pleasure is on a par with that of a snake (and that’s being unkind to the snake, who can patiently lie in wait for its prey when necessary).
Girls are fortunate in that, since they undergo puberty at an earlier age, their prefrontal cortex will be fully developed by their sophomore or junior year in most cases. The danger period generally lasts through the latter years of middle school and/or their freshman year (though there are always outliers). Boys aren’t as lucky - for much of high school, and especially during their all-important (for colleges) sophomore and junior years, they’ll be at their worst insofar as rational decision-making and their motivation to complete unpleasant-but-necessary work is concerned. This hurts their performance in school, and increases the likelihood of their making decisions that’ll foreclose a lot of options even when they’ve matured - whether because they earned poor grades, because they dropped out of school, or because they’re living in an overcrowded prison cell.
There are exceptions of course - many boys don’t have any of the above issues (strong impulse control is a heritable trait, so often these boys will also have parents who make sure they’re not going off the rails). Some will be fortunate enough to undergo puberty sooner - these are the kids who have so-so grades in middle school or freshman year, but straighten out in high school. Others will mostly avoid such issues in high school, but then make poor choices in college.*
*I suspect, although this is just politically incorrect conjecture that hasn’t been confirmed or denied by academic research, that those who commit sexual assault in college (a group, we can all agree, with terrible impulse control) probably went through puberty a year or two later (on average) than the general population. I don’t want to be misunderstood - I’m saying that many such people likely went through puberty later, and not that late bloomers are all rapists.
The upshot is that, as the neuroscience shows, boys tend to make poor decisions at a higher rate than girls in high school. This disparity is seen in the gender distribution you’ll find among college freshmen each year (skewed towards girls) and I suspect the higher dropout rates observed among boys are a result of the same phenomenon.