Islamic State (Isis) has scrapped science and literature from the curriculum of schools in Raqqa, its Syrian base of operations, replacing it with indoctrination in hardline theology and jihad, according to a Syrian human rights group.

After closing schools for months IS will reopen educational establishments, but is forcing children to learn a new curriculum in which the teachings of Wahhabism and 'Tawhid and Jihad' take centre stage, said campaign group Raqqa is Being Slaughtered Silently in a report.

Tawhid refers to Islamic monotheism, and jihad to religious war. The name Tawhid and Jihad was the name of the terrorist group formed by Jordanian radical Abu Musa'ab al-Zarqawi, one of IS's precursors.

IS has published documents stamped with the group's black and white logo outlining its new educational policies, as it focuses its efforts on imprinting its brutal form of conservative Islam on children's minds.

The group is also demanding that all teachers in the area attend specific mosques within two weeks where they must repent the "infidel" state education system.

The Syrian campaign group reports that property allegedly belonging to teachers not currently in Raqqa has been seized by IS, and that even retired teachers will be forced to reject the education system.

The group alleges that IS is attempting to return education in Syria to the "dark ages".

Last week, IS released footage of a camp in Syria where children as young as five were being trained in Islamist theology and combat techniques.

It also emerged that IS was providing English language teaching for the children of foreign adherents, on subjects including Islamic theology and mathematics.

Muhammad Ibn Abd al-Wahhab founded Wahhabism in the in the 18th century. It is a puritanical form of Islam that advocates a strict adherence to what its followers regard as the fundamental tenants of Islam.

It is the officially backed form of Islam in Saudi Arabia, and experts believe that IS's theological roots lie in Wahhabism.

"It is a kind of untamed Wahhabism," Bernard Haykel, a scholar at Princeton told the New York Times. "Wahhabism is the closest religious cognate."