"This is war too," murmurs an ex-child soldier in southern Sudan, stone-faced and staring blankly at a placard reading: "Let all children go to school ... Leave no child behind."
A year after the end of two decades of fighting with regimes in Khartoum in a conflict that claimed 1.5 million lives and displaced four million people, south Sudan has declared war on illiteracy.
The region's ruler Salva Kiir has decreed that all school-going age children report to school this week under a 32-million-dollar (26.4-million-euro) UN-backed initiative to double the number of children in school this year.
Bare-footed youngsters, traumatised by years of conflict and malnourished by hunger, now crave High Street careers and are eager for the chance to learn.
"When I grow up, I want to be a pilot," said 12-year-old Oliver Aligo, an HIV/AIDS orphan, who wants to learn English to speak the international language of aviation for future professional but also personal reasons.
"I want to go to school to learn proper English so I can follow storylines when I watch movies," he said with a sly grin as clusters of other children milled about exclaiming their preferred profession.
"And me a teacher or a doctor," threw in one excited child, dwarfed by his oversize UNICEF T-shirt.
According to UN estimates, only about 500,000 of the region's estimated 2.2 million school-age children are currently enrolled in primary schools.
UNICEF expects that figure to double this academic year, which started on Monday, as part of an effort to slash illiteracy level from its current whopping rate of 76 percent.
And so on Monday, scores of previously uneducated children carried blue schoolbags, books and pencils for their first lessons.
At break, there were squeals of joy as the pupils noisely tossed around newly delivered basketballs, footballs and volleyballs at the school overlooking the rocky Jabel Kujur hills.
"Never mind there is no basketball court here ... but it is all like a fresh start," said a UNICEF official at Juba's Buluk Primary School, expressing fears that some playgrounds in the region may be heavily mined.
While traditions barred girls from education, conscription into numerous militia and ex-rebel Sudan People's Liberation Movement (SPLM) kept boys away from school.
"The war left southern Sudan education in ruins," said UNICEF deputy chief Rima Salah, noting that only 25 percent of children attended school during the 21 years of north-south conflict, Africa's longest-running civil war when it ended in January 2005.
"Only one in 100 girls will finish primary school," she said. "There are unique and enormous needs here. Peace has to be more than just silencing the guns.
"After all these years of war, people - especially children - need to see a real difference. A new generation of people will be the ones to make this peace work," Salah said.
Kiir, who took over leadership of the ex-rebel Sudan People's Liberation Movement (SPLM) on the death of its founder John Garang in a helicopter crash last year, said education was the best route to avoid the crushing poverty that has afflicted south Sudan for generations.
"When I was growing up, a pen was my hoe," Kiir told hundreds of excited children in Juba, a neglected outpost on the shores of the River Nile that serves as the capital of the semi-autonomous region.
"If you use your pen properly you will never go to bed hungry," said Kiir said on Friday, who is also first vice president of Sudan's national unity government established after the peace deal was signed.
City dwellers are also excited, united in the new effort to educate children.
"This is the only sector in which the southern Sudan tribes can unite," said a western diplomat working here, where tribal warfare has hampered unity, notably between the Dinka and Nuer.
"I am so excited, I will give my all to ensure that children go to school," said 68-year-old Juba resident Salome Yuan.
"Some of us never had the opportunity to study, to compensate we will work together to ensure our children benefit from education," said a man who gave his name as Josphat.
The region's Education Minister Michael Miir Hussein said his department's 140-million-dollar (115.6-million-euro) budget was second only to the military's.
"It is going to be a hard war to ensure every child goes to school, but we are determined," said Hussein, a medical doctor by training.
"We have problems ... but we are determined to overcome these obstacles," he added.
Despite the massive obstacles, there is hope although some hopes may be ultimately unattainable.
"One day, perhaps schools in southern Sudan will be like Hogwarts," mused a UN official, referring to the fictional academy in the best-selling Harry Potter series that produces accomplished wizards.