The three finalists for the World's Children's Prize 2011 were:
Cecilia Flores-Oebanda, from the Philippines, for her untiring work to combat child labour and human trafficking, and for her support for girls who have been forced to become sex slaves.
Monira Rahman, from Bangladesh, for her fearless fight to save girls, in particular, who have been disfigured as a result of attacks using acid or petrol.
Murhabazi Namegabe, from the Democratic Republic of the Congo, for his perilous struggle to free children who have been forced to become child soldiers and sex slaves.
The Queen awarded the prize to the winner, Murhabazi Namegabe. Find out more about the winner here.
The Queen is the first Honorary Adult Friend and patron of the World's Children's Prize.
The World's Children's Prize contributes towards a more humane world, in respect of the rights of the child and democracy. Schools with 24 million pupils in 101 countries are involved. Each year, millions of children learn about rights of the child, democracy and global friendship.