Somali schools should stop using "un-Islamic" textbooks distributed by the United Nations, a spokesman for the Islamist group al-Shabab has said, BBC reported.
Sheikh Ali Mohamud Rage urged Somalis not to send their children to schools which use such books.
A BBC reporter in the capital Mogadishu says that despite the violence in the country, many schools still operate - and most use UN textbooks.
Extreme Islamist groups control most of southern Somalia.
The writ of the UN-backed government only runs in small parts of Mogadishu.
"Some UN agencies like Unesco are supplying Somali schools with textbooks to try to teach our children un-Islamic subjects," Mr Rage said at a graduation ceremony for Koranic students, reports the Reuters news agency.
"I call upon all Somali parents not to send their youngsters to schools with curriculum supported by the UN agencies."
The BBC's Mohammed Olad Hassan in Mogadishu says it is not clear whether other al-Shabab leaders share his view.
Our reporter says some schools use textbooks from Saudi Arabia.
Al-Shabab is accused of having links to al-Qaeda.
On Thursday, it carried out a double suicide bombing, killing 17 African Union peacekeepers in Mogadishu.
Somalia has not had an effective national government since 1991.
Years of fighting and anarchy have left some three million people - half the population - needing food aid.