A recent report was made public by REUTERS that the Islamic States in Iraq in the past had some education centers of sort, where some kidnapped children were trained to build a network of child informers and fighters used by the jihadists to support their military operations.
This is coming from REUTERS and information from a worker at the former orphanage where they were housed, reveals that children ranging from age 3 to 16 and predominantly Shi'ite Muslims or minority Yazidis begin to refer to their families as apostates after they have been schooled in Sunni Islam by the militant fighter.
They are believed to have many training sites across the city of Mosul in Iraq, where the young boys are trained to absorb the group's ultra-hardline ideology.
According to Reuters, "Islamic State withdrew before Iraqi forces launched a U.S.-backed offensive in October to retake the city, but during a Reuters visit last month there were still reminders of the group's attempt to brainwash dozens of children."
"A saying attributed to the Prophet Mohammed is painted in black on one wall, urging children to learn to swim, shoot and ride horses. Inside the building is a swimming pool, now dry and full of rubbish."
"In another room sits a stack of textbooks Islamic State had amended to fit its brutal ethos.
Arithmetic problems in a fourth grade maths book use imagery of warfare, while the cover bears a rifle made up of equations. History books focus exclusively on the early years of Islam and emphasize martial events."
Another textbook entitled "English for the Islamic State" includes ordinary words like apple and ant beside army, bomb and sniper. Martyr, spy and mortar also appear alongside zebra crossing, yawn, and X-box.
"The word "woman" is depicted by a formless black figure wearing the full niqab covering. All faces in the books - even those of animals - are blurred, in keeping with an Islamic proscription against such images."
The orphanage worker, who was cowed into staying on after the militants took over in 2014, said girls who were brought to the center were often married off to the group's commanders.
The man asked not to be named for fear of reprisals by Islamic State, which still controls the entire western half of Mosul. He was shot in the leg during recent clashes.
He said the militants, mostly Iraqis, taught the Shi'ite children how to pray in the tradition of Sunni Islam and forced the Yazidis to convert.
They memorized the Koran, were taught to treat outsiders as infidels and conducted physical exercise in the yard, which has since grown over.
One of the boys, Mohammed, was killed last summer during the battle in the city of Falluja, west of Baghdad, he said, recounting how the other children wept upon learning the news.
A few weeks before the Mosul offensive began, Islamic State canceled lessons and sent the boys to guard an airfield near Tel Afar which pro-government forces later seized, he said.
"I told them, 'If you see the army, drop your weapons and tell them you are orphans. Maybe they will spare your lives'".