It seems to me straightforward there is a positive relationship between educational level of individuals and their aspiration to power. Then, a negative one between education and the willing to be ruled without any say in that matter. Ergo, a positive relationship exists between average national level of education and democracy. The relationship may suffer of reverse causality (the causality goes in two ways): not only more educated individuals push for and determine democracy eventually, but also more democratic countries are ruled by elected elites that are forced by the fear not to be elected again to implement policies in favour of the collectivity (among them providing education). However, history teaches, often, that who holds power is generally owner of knowledge – since Maya’s society. That knowledge that in monarchies was only a privilege of political establishment, inherited from father (king) to son (prince). Knowledge that then began to spread among the population, giving rise to a new lobby of bourgeois (middle-class) that changed the States, France and Europe since 1776. With knowledge spread universally, the ideas are heterogeneous, all equally powerful and worthy of attention. The natural result is democracy, a nonviolent and synthetic solution of conflicts otherwise flooding in a never ending state of war. Hence, if the logic above had a sense, education would cause, in the long run, democracy. Finally, after a democratic system is established, only then the reverse causality would begin its puzzling action. Just few considerations/enigmas:
1) Does the type of education matter? Is studying math stimulating the hanger of power and democracy and the anger for their lack just like literature & history are?
2) Is interest of democratically elected elites to lower the level and the quality of education in order to preserve the power in the long run?
3) Is education related with the revolutions in the Middle East? (Arab experts needed urgently!)
Like always, I positively accept insults, critics, and, mostly, I am starving for references!
DEVELOPMENT IN PROGRESS 
My very personal opinions are that:
1. it’s not much about “what” u study, but “how” u study. When school encourages critical thinking and open dialogue, students will grow up as aware citizens (in our sense of the term). then the big problem becomes the access to a good information, which is another story…
2. the demolition of our school system by our beloved prime minister Mr. B’s govt is the evidence for a “yes it is!”. But the effect of lowering the education level will show up in many years, so this can not be a strategy for Mr B.’s government direct benefit itself…
3. no revolution in history has been done by illiterate people. there’s always some vanguard of “thinkers” who starts the fire… bloggers in these cases are part of this vanguard. so i say again “yes, it is!”
ciao Toni!
PS: democratic governments don’t provide education because of their fear of not being re-elected. they provide education because they believe in democracy. Those who provide education for fear have some democratic deficit actually