By Mark Doyle
BBC World Affairs correspondent
A UN report says only about 500 girls and 2,000 boys complete primary education every year in southern Sudan - the lowest rate in the world.
Southern Sudan has been destroyed by the civil war
The report by the Unicef children's agency says the region has been badly affected by the war, although it is engaged in peace talks now.
Unicef wrote the report with the rebel SPLA, the de facto government of the south.
SPLA leader John Garang said some of the report's statistics were appalling.
'Mountain to climb'
While conflict continues in the western Darfur region between pro-government Arab militias and ethnic African rebels, the rest of southern Sudan is, paradoxically, engaged in peace talks.
SPLA rebels and the government are now talking not fighting
In a country the size of western Europe, these contrasting situations are perhaps no surprise.
Southern Sudan, the Unicef report says, has the youngest population profile in the world; there's a high fertility rate but a low proportion of adults because of famine and war.
Only some 2,500 of those children across the whole of southern Sudan finish primary education every year.
"We always knew we had a mountain to climb; now for the first time, we have a map of the mountain," Mr Garang said.
"Of course, unless the peace talks succeed and are extended to the conflict Darfur, that climb may never begin."