Siobhan Bell was elected Lewisham’s Young Mayor – the first female to reach the post.
The 17 year-old from Crossways Academy won after taking 1,948 votes and was joined by a female deputy.
The business student ran on a manifesto which promised constructive changes in environment, health and education and homelessness.
The new Young Mayor said: 'I’m so excited. It’s good girls have been elected.
'The past two years have been boys, but now we’ve got a chance to show we can do the job and do it in a different way.
'The fact we’re black as well shows people what can be done if you work hard.
'I’d like to thank everybody who supported me and helped in my campaign.'
Steve Bullock, the adult Mayor of Lewisham, said: 'I am delighted that once again the young people of Lewisham have shown they believe in democracy.
'We’ve proved wrong those who said young people cannot be engaged and have lost touch with democracy.
'I congratulate Siobhan on a great campaign and I hope she will continue to give the borough’s young people a genuine voice.
The new deputy Young Mayor was announced as Luziane Tchiegue-Nouta, 15, from Sydenham School at a ceremony held in the council’s Civic Suite on 12 October.
In total 7,967 youngsters voted in the elections – a 43 per cent turnout.
Bridget Prentice, MP for Lewisham East, and Democracy Minister at the Department for Constitutional Affairs said: 'Clearly Lewisham is leading the way in helping young people express their views on things that matter to them. That’s what electing a Young Mayor is all about. It’s what politics should be all about.
'I’m very proud of Lewisham’s young mayor and tell other councils across the country about it. The Government’s aim is to get more young people involved in the democratic process and that means firstly getting them registered to vote, then they can have their say, just as Lewisham’s young people have done today.'
The Young Mayor received 1,948 votes, while her deputy polled 1,434. Third place went to Margaret Oybambi, 16, from Deptford Green school, with 684 votes and in fourth was Jasmine Jarvis, 14, from Sedgehill school with 583.
Guests included Wilf Petherbridge, last year’s Young Mayor, Bridget Prentice MP, Steve Bullock, Mayor of Lewisham and delegates from the schools council in Sofia, Bulgaria.
Councillor Robert Massey, Cabinet Member for Children and Young People, said: 'Once again we’ve demonstrated how enthusiastic our young people are about engaging with issues which really matter to them.
'In Lewisham we give our young people real power which past young mayors have used excellently and I’m sure Siobhan will do just the same this year.'