The ISIS documents, some shared with CNN by researcher Aymenn Al-Tamimi, give a window into the bureaucracy of the self-declared caliphate.

Last summer, ISIS fighters swept through the Iraqi city of Mosul. Once they took power, leaders wanted to show they could bring stability allowing daily life to resume. So, they quickly reopened the University of Mosul, albeit under a radically altered curriculum.

Notices went out that classes would resume on 24 Dhu al-Hijjah 1435 in the Islamic calendar (or October 18, 2014, in the Western calendar), about four months after ISIS overran the city.

But some subjects would be banned -- democracy and political thought, also hotel management and tourism and archaeology.

"The banning of archaeology is not a surprise," says Al-Tamimi, who is a Shillman-Ginsburg Fellow at the Middle East Forum at the Interdisciplinary Center Herzliya, in Israel. "We see that reflected in ISIS destruction of ancient artifacts. ISIS regards pre-Islamic artifacts as relics from the 'period of ignorance', jahiliyah. Their main concern with archaeology is that it would become a subject turning to idol worship, which is strictly forbidden in Islam.

"Hotel management and tourism may seem strange as first. But there are no hotels under ISIS. They have all been taken over and shut down, either rented out or become places to house families."

Mosul University still has the same professors and teachers, Al-Tamimi says. "But now teachers are subjected to Sharia sessions, to learn what is and what is not acceptable to ISIS. So, they have preserved the prior system but within ISIS Sharia law conditions."

As per al-Tamimi, a general theme for ISIS is that they try, initially when they seize control, to portray themselves as more just, more fair to the inhabitants than the previous ruler.

"For example, in Syria, the first thing ISIS did was lower the price of bread. This is as much about winning over the population as it is about religious rulings."