racefortheironthrone:

I’ve discussed this before here, but given their level of technology and literacy, Essos must have more of an education system than is shown in the text. 

There’s a couple possibilities:

• Greco/Roman slave-tutoring: this fits the Free City’s social structure, even if that social structure isn’t super well-suited to their level of technology but w/e. Well-educated slaves tutoring the elite philosophy, rhetoric, and the rest of the trivium and quadrivium is certainly a long-lasting “successful” model of education, so there you have it. 
• Local Academies: This is more likely in Braavos and Braavos-centric cities that don’t have slavery. I wouldn’t be surprised if the Essosi academies are A. more focused on Valyrian “humanism” as opposed to the Citadel’s relentless focus on empiricism, and B. more focused on applied sciences needed for finance, commerce, and high-end manufacturing than the Citadel’s trade-school-approach to feudal administration. 

I don’t go here, but I’d like to add that religious schools led by the priests (especially in Norvos or Qohor where there’s a strong central religious order) are also a strong possibility. Merchants and artisans in big cities could also band together to create the equivalent of guild schools, tutoring children to young for apprecticeships in mathematics, finance, and craftsmanship and helping share new techniques and styles. Smaller towns might have local proto-grammer schools to educate upper class children more generally without the niche focus of, say, a weaver’s school or a banker’s. 

Ancient Greece and Rome both had widespread systems of private schools in addition to home tutoring, and teachers both free and enslaved taught a variety of subjects to children of all ages up to what we might consider college. It all depended on how much money their parents were willing to shell out, and what subjects they wanted their children to learn. In Valyrian city states we might see anything from small schools with classes of a dozen upper class young boys, to huge schools of philosophy mirroring those established by people like Aristotle, to physical education classes teaching wrestling and refined combat. 

Systems of patronage are also powerful forces of education. In more mercantile circles this might mean apprenticeships being carefully managed to find the best talent and nurture innovation, and the wealthy shopping around for new artisans to patronize. It could also mean philosophers and other intelligent free men being paid to lounge around and pontificate and eventually set up their own schools to tutor rich young adults in higher rhetoric and thought, or salons of artists, poets, and thinkers being run by wealthy women who dole out money to their favorites. When knowledge and the arts are in style they get nurtured by those trying to look trendy.