@Amalvi:

I don't think it impossible at all. If you follow/read TAMnI/TAKnR, the students number is so big yet the city able to hold that number of student.

I agree with you, the Enrollment to the Academia City itself is hard, and the curriculum there is totally on other level. A University level material in outside already taught in Academia City's Middle School

And I live in one of the most populated City in the earth (Jakarta at 2010 there about 9,608 million people live here)

So, 500.000 student lived at that Academia City is quite believable for me. 

Speaking of which; There's about 831.300 people at that Island (there's a City and a Town in that island). 93% of the Population at Academia City while 7% at Верный (which surprisingly able to supply the Island with the food stocks every year and some of the surplus sold to other Island in Caelifer). Within that 93% population in Academia City, 82% of them students, while 18% is the others.

[b]EDIT[/b]: Off course i wanna see how your imagination Map of Academia City look like