A Palestinian teacher has won a $1m (£707,000) global teaching prize - with the award announced in a video message by Pope Francis.
Hanan Al Hroub grew up in a Palestinian refugee camp and now is a teacher of refugees herself.
She specialises in supporting children who have been traumatised by violence.
The winner was announced at an awards ceremony in Dubai, with a video message of congratulation sent by Prince William.
Pope Francis sent a message saying that teachers were "the builders of peace and unity".
Ms Al Hroub told the audience that "teachers could change the world".
Growing up in a refugee camp near Bethlehem, Ms Al Hroub now works with refugee pupils, with an approach using play that is aimed at resolving violence and tension.
"I am proud to be a Palestinian female teacher standing on this stage," she said after receiving the award.
She says she will spend the prize money on supporting her students.
Prince William spoke of the "incredible responsibility" of teachers and that they could "influence, inspire and shape a young person's life for the better".
There was a UK finalist, Colin Hegarty, a maths teacher from London who has created a website with interactive online maths lessons.
The finalists for the Global Teacher Prize included teachers from India, Kenya, Finland and the United States.
Created by the Varkey Foundation, the charitable arm of the GEMS international education firm, the prize and Oscars-style ceremony are intended to raise the status of the teaching profession.
The audience for the event included Hollywood stars such as Salma Hayek and Matthew McConaughey and political figures including former UK prime minister Tony Blair and the vice president of the United Arab Emirates Sheikh Mohammed bin Rashid Al Maktoum.
The top 10 finalists were invited on stage by a video message from physicist Stephen Hawking and were congratulated by video messages from US vice-president Joe Biden and former US president Bill Clinton.
Sunny Varkey, founder of the Varkey Foundation and who created the prize, said he hoped that Hanan Al Hroub's story would "inspire those looking to enter the teaching profession".
The finalists included:
•Maarit Rossi from Finland developed her own method for teaching maths. Finland has some of the best maths results in the world in international tests, but Ms Rossi's classes are high achieving even against Finnish standards.
•Aqeela Asifi came to Pakistan as a refugee from Afghanistan and is teaching refugee children in a school that she created.
•Ayub Mohamud, a business studies teacher from Kenya, has reached the finals with a project to discourage violent extremism and radicalisation.
•Robin Chaurasiya from Mumbai in India founded an organisation to teach and support teenagers from the city's red-light district.
•Richard Johnson, a science teacher from Perth in Australia, set up a science laboratory for primary school children.
•Michael Soskil from Pennsylvania in the United States, a previous winner of the Presidential Award for Excellence in Math and Science Teaching, has motivated his pupils by linking them with projects around the world.
•Kazuya Takahashi from Japan has developed innovative ways to teach science and to encourage global citizenship.
•Joe Fatheree from Illinois in the United States has pioneered teaching projects using 3D printing, drone technology and using online games such as Minecraft.
Sunny Varkey, founder of the Varkey Foundation, told the international education conference that the prize was intended to bring greater public recognition to the importance of teachers.
"My hope is that children from around the world will watch Sunday's ceremony and think about what their own teachers do for them," said Mr Varkey.