In the introduction it is stated that there are eleven established/registered schools. There are writings for six of them. I don't think we need a new writing for Hogwarts... so that means seven have been located and defined.
- Hogwarts School of Witchcraft and Wizardry - Great Britain
- Beauxbatons Academy of Magic - France
- Durmstrang Institute - Northern Europe (possibly Estonia, Latvia, or Belarus)
- Mahoutokoro - Japan
- Uagadou - Africa (possibly Congo/DRC)
- Castelbruxo - Brazil
- Ilvermorny - United States
Do we know anything of possible location or names of the other four schools? I know Koldovstoretz was mentioned as school in Russia, but is that still canon?
- Koldovstoretz - Russia (maybe depending on current canon)
The final three are my guesses based on the population and geography on the world.
- Name Unknown - China (based on population)
- Name Unknown - India (based on population)
- Name Unknown - Australia (based on geography)