As big of a proponent of continued education as I am, I have to concede that sometimes dropping out is the best, or even only thing someone can do. I should probably also note that this is limited to particularly extreme cases; the overwhelming majority of the time, staying in school is the best option.

Rather than list numerous different examples of circumstances where dropping out would be the best option, I'm just going to throw out a general condition that could be applicable to numerous circumstances. Dropping out is the better option when immediate needs are such that the future cannot be considered. Education is treated (incorrectly in my opinion, but thats another debate entirely) as training (or at least prerequisites) of sorts for future career opportunities. As such, it is only worth pursuing in this climate when one can reasonably assume that future career opportunities are going to be an option, and only when pursuing said opportunities will not entail sacrificing something important to you.

Consider a situation where the families primary breadwinner dies, or is otherwise injured and rendered unable to work. All of the benefits available may not be sufficient to support the family under these circumstances without massive sacrifices- say, the college funds for the kids. In this situation, it would be entirely reasonable for a high-school aged child to drop out of school and enter the workforce, even at minimum wage, to support the family. Doing this could be the difference between the siblings having the opportunity to go to college or not.

Consider a situation where both parents are killed- elder sibling is, say, a senior in high school and 18, with a couple of younger siblings. That elder sibling may well be willing to sacrifice his education and- again- enter the workforce, just to keep his family together. Some may argue that the family would be better off if they split up into different foster homes, but try telling that to a family- particularly a group of siblings who have lost their parents and see one another as all they have left.

There are other situations, all equally rare and unlikely (but none nonexistent) where this can apply. If immediate needs trump future concerns, or if continued education would require sacrifices one is unwilling to make, then dropping out is the best option. This is rarely the case, but it does happen at times.