This particular set of worlds (ScatterWorlds working title, very subject to change), is very primitive; I think of each race being slightly more advanced than hunter/gatherer societies, but are certainly not medieval.

Childhood schooling isn't something I've touched too much on yet, because I think with these races being so early in their development, they haven't got too much to teach, apart from social mores, labor skills, and art. I'm thinking that, while tumans were the first to create a written language, they specifically use it for poetical purposes, and less for conveying facts or historical accounts. The physical form of a book in particular is too advanced for them, but I'm sure they have created clay tablets for writing on.

I think none of the three races care too much about history and don't record much, which I think makes such concepts more curious and intriguing when they do find artifacts and markers of other civilizations. Seeing evidence of someone else's handiwork in a previously unexplored area sends them into new lines of questioning they'd never considered.

The way I imagine these three races is that each lives on a separate homeworld where they are limited by their resources and can only achieve some particular level of technology and sophistication, and it is only when they meet and find other worlds of abundance that they combine their skills and create cities and new technology. Once technical knowledge starts to take off and spread, it would then become necessary to have schooling, at least in the form of trades apprenticeships, but possibly more academic forms for those looking to improve life, acquire knowledge, and explore.

Since you mentioned architecture, I'll add as a little aside that the tumans of course make their huts out of clay bricks, while bumans, having abundant wood on their homeworld (something akin to redwood forests), make treehouse villages, and the lumans, having cotton-like plants on their world, are primarily clothiers, and live in tents. When the three races meet, their cities are a smorgasbord of architecture that combines those three main styles elaborately and elegantly. When I get to designing city layouts, I expect it to be a trip.