258 million kids out of schooling: UN

The U.N. deputy chief said Friday there is an "alarming" crisis in education, pointing to the 258 million children under the age of 17 who are not going to school — and only 49 percent completing secondary education.

In addition, about 770 million adults are illiterate, most of them women, Deputy Secretary-General Amina Mohammed told the U.N. General Assembly on the International Day of Education.

She said the situation is "alarming," not only because of the millions who aren't getting an education — and never did — but also "because of the crisis in the number of children, young people and adults who are in education, but not learning."

Former British prime minister Gordon Brown, the U.N. special envoy for education, has said he continues to be "shocked" that more than 400 million children leave school for good at age 11 or 12 and "800 million children are leaving the education system without any qualifications worth their name."