African leaders gather in Kigali this week at the Sub-Saharan African Education Conference, to discuss their vision for education beyond 2015.

The conference, organized by UNESCO and its partners in the Education For All (EFA) movement, provides an opportunity to reflect on the progress that has been made in attaining the EFA goals set in 2000 and the challenges that remain.

Sub-Saharan Africa has made big strides in education over the past two decades. Governments have combined political will with positive action to get girls and boys into school and provide them with a quality education. The benefits of investing in education in the region are evident and the results are tangible.

In Rwanda, investment in education reduced the number of out-of-school primary aged children from 14.6 percent in 2002 to 1.3 percent in 2012. Special funds were established to ensure that orphaned children benefited equally from educational opportunities.

Rwanda also expanded lower secondary schooling, with the gross enrolment ratio more than tripling since 1999 to reach 37 percent in 2012. The introduction of a nine year basic education cycle and the elimination of fees for lower secondary school boosted the number of lower secondary students by 63 percent between 2008 and 2010.

The government is now working towards 12 years of free education for all.

This is good progress and there are plenty of similar examples. Yet, the situation remains fragile across the continent, and, in many areas, the momentum of the past decade has stalled. We need to kick-start the movement again and prevent the hard-won gains from being lost.

UNESCO statistics show that 30 million of the world's 58 million out-of-school, primary age children live in Sub-Saharan Africa. Despite some progress, girls are still at a disadvantage in the region, as for every 100 boys enrolled, there are only 92 girls enrolled in primary education and 84 girls in secondary education.

Several factors have contributed to this.

Sub-Saharan Africa's school age population is growing faster than in any other region - up 29 percent since 2000, according to UNESCO. This translates into an extra 49 million children and compares with a fall of almost ten percent in the rest of the world. Governments may be working hard, but alone, they simply cannot keep up with rising demand.

Conflict is another obstacle to quality education in the region. Out of 33 conflict-affected countries in 2012, 13 were in sub-Saharan Africa. Young people in many places paid - and continue to pay - a terrible price, often recruited as child soldiers or slaves, and even targeted because they and their families dared to even seek an education, as in the case of Nigerian schoolgirls last year.

Most recently, the Ebola outbreak closed schools in Guinea, Liberia and Sierra Leone for several months denying education to some five million girls and boys. Research indicates if they are out of school for a year, over half may never return. Ebola threatens years of educational progress in West Africa where literacy rates are already low and school systems are only now recovering from years of civil war.

These are daunting realities. But we must not forget that education is both a basic human right and a smart investment. It is important that organizations like the Global Partnership for Education, which is working to improve education for the world's poorest, continue to focus on these fragile and often conflict-affected countries. Almost half of the Global Partnership's funding in 2014 went to countries that fall into this category.

Education is critical for development and helps lay the foundations for social well-being, economic growth and security, gender equality and peace. It also provides the frontline of defense in tackling diseases such as Ebola, by teaching children about how they can protect themselves and their families.

Governments know this and have been working hard to overcome the obstacles. Education fees, for example, have been or are being eliminated in several countries, making it easier for parents to send their children to school. Education budgets have been increased, and more teachers are being trained.

Looking again at Rwanda, investment in teachers has resulted in an increase in the share of qualified teachers from 49 percent of the teaching force in 1999 to 98 percent in 2011.

Rwanda has also been pioneering an innovative computerized school book distribution system that puts schools in control. This new system, funded by the Global Partnership for Education and other development partners, increases accountability and removes obstacles that previously prevented learning materials from getting to Rwandan students.

Furthermore, Rwanda has improved tax collection, increasing the share of tax revenue as a proportion of GDP from ten percent in 1998 to 13 percent in 2011, allowing the government to boost spending per primary school child from $72 in 1999 to $81 in 2011.

Such determined effort and commitment must be acknowledged and supported.

We urge all stakeholders to keep education in Sub-Saharan Africa at the centre of national and international development agendas. This means working ever more closely with the governments of the region - along with parents, teachers, young people and the private sector. It also means ensuring that aid levels for education are at minimum maintained, and increased where needs are greatest.

Every child has the right to go to school. It is the responsibility of all of us to make sure that happens.

Irina Bokova, Director-General of UNESCO and Julia Gillard, Chair, Global Partnership for Education