Malala Yousafzai may be one of the best-known students in the world, but she is also a teacher.  This month she will mark her 16th birthday by coming to the United Nations and sharing an important lesson about education – particularly for girls around the world.  Malala is the courageous young education rights campaigner from Pakistan who was targeted and shot by extremists on her way to school.  After a long road to recovery, Malala is back and determined to keep making her voice heard.On 12 July, Malala will be joined by hundreds of students from more than 80 countries in a unique Youth Assembly, where diplomats will take a back seat as young people take over the UN.  They will gather to issue a global call for quality education for all. Education is a fundamental right, a Millennium Development Goal (MDG) and crucial to mutual understanding and global citizenship.  Many of us did not have to learn this lesson from a book.  We lived it.  As a young boy in war-torn Korea, my school was destroyed.  My classroom was in the open under a tree.  We had little to eat, but we were hungry to learn.  Our parents and our government knew the value of education.  That understanding transformed my life and my country.In today’s knowledge-based society, education is a foundation for the future we want: a world without poverty, violence, discrimination or disease.  Building this future will require a new, concerted push. That is why I launched the Global Education First Initiative, with three priorities: to put every child in school; improve the quality of learning; and prepare children to grow up to be global citizens. Despite important gains, we have much work ahead of us to meet our education goals.  Today’s youth population is the largest in history. We must make the most of this pool of talent, energy and ideas. Yet, there are still 57 million children out of primary school. Many live in countries embroiled in conflict. More than 120 million young people between the ages of 15 and 24 lack basic reading and writing skills – the majority of whom are young women.  In a swiftly evolving job market, too many young people leave school without the skills to earn a living.In far too many places, students like Malala and their teachers are threatened, assaulted, even killed.  Through hate-filled actions, extremists have shown what frightens them the most:  a girl with a book.We must do all we can to ensure that schools are safe and secure learning spaces.  Nowhere in the world should it be an act of bravery for an adult to teach or a girl to go to school.  When women and girls are educated, they accelerate development in their families and communities.  For every extra year of schooling, a girl increases her future earnings by up to 20 percent.  Many other statistics point to the importance of education.  Economies grow.  Health improves.  Nations rise.  But I also take my cue from listening to the aspirations of people.  Wherever I travel, I ask women and men what the United Nations can do for them.  The answer is very often the same:  Education.In refugee camps, people tell me: "Get my children back in school.” In countries hit by earthquakes and other disasters, people insist: "Don’t worry about me.  Re-build the schools so my children can learn.”Education is the pathway to saving lives, building peace and empowering young people.  That is the lesson that Malala and millions like her are seeking to teach the world.  International partners and governments must listen and act.As the global community works to speed up achievement of the MDGs and craft the post-2015 development agenda, we must ensure that we meet our children’s dreams and aspirations for the future.On Malala’s birthday let us pledge to deliver the best gift of all – quality education for every girl and boy in the world.Ban Ki-moon is Secretary-General of the United Nations