Education key, Michelle Obama tells London schoolgirls
US First Lady Michelle Obama has told pupils at a girls' school in east London that education is the "ultimate key" to their success.
Greeted by screams and cheers, she talked about her own working-class background in Chicago in a speech at Mulberry School for Girls.
The visit is part of her global initiative to promote female education.
Accompanied by her two daughters, she also met Prince Harry at Kensington Palace and had tea at Downing Street.
Mrs Obama told pupils at the school in Tower Hamlets the world needed "more girls like you to lead our parliaments, our courtrooms and universities".
In a speech, she said: "With an education from this amazing school you all have everything, everything you need to rise above all of the noise and fulfil every last one of your dreams.
"And it is so important that you do that, not just for yourselves but for all of us. Because you all have a unique perspective, you have a unique voice to add to the conversation."
Ben Geoghegan, BBC News
This was a very personal - and at moments, emotional - speech, delivered directly to the girls at Mulberry School rather than for the ranks of cameras at the back of the room.
The school is in an area of high deprivation. Most of its students are from the Bangladeshi community and, for most, English is an "additional" language.
The First Lady compared her upbringing with theirs. As a black teenager on the south side of Chicago she remembered people telling her not to set her sights too high. She broke down the barriers to success.
She urged the schoolgirls in east London to do the same and to fulfil their dreams.
The "ambitious, confident and principled" students at the Mulberry School were inspired.
The question is whether Mrs Obama's message will be heard in those parts of the world where girls don't go to school at all.
In her address, Mrs Obama spoke of her own upbringing, saying in her youth there were few black women in positions of power.
But she said her parents realised education was the "ultimate key" to success and she could be successful if she worked hard at school.
She said: "Through it all my parents fully expected us to do both: to achieve our dreams and be there for our family.
Mrs Obama also met International Development Secretary Justine Greening and Education Secretary Nicky Morgan. They announced the UK would be backing Mrs Obama's Let Girls Learn initiative to improve access to education in countries such as Sierra Leone, Liberia and the Democratic Republic of Congo.
Tea at the palace
Earlier the first lady, accompanied by her daughters Sasha, 14, and Malia, 16, and mother, Marian Robinson, met Prince Harry for tea at Kensington Palace.
Their meeting came two years after the prince attended a mother's day tea for military mothers with Mrs Obama in the US.
A Kensington Palace spokesman said: "They discussed their shared interest in support for veterans and their families. Prince Harry was also interested to hear from the First Lady about the Let Girls Learn initiative."
They later spent about 45 minutes with Mr Cameron and wife Samantha in Downing Street, where they arrived in a seven-vehicle convoy.
Writing in the Financial Times, Mrs Obama said figures which suggested more than 62 million girls across the world did not go to school were a "heartbreaking injustice".
Forced marriages, early pregnancies, abuse and sexism were some of the obstacles to education faced by girls around the world, she said.
"That kind of life is unthinkable for the girls in our lives, so why would we accept this fate for any girl on this planet?" she wrote.
The US party will fly on to Italy after the London trip to meet US armed services families based in Europe, and to continue to promote Mrs Obama's work to encourage healthy eating among children.