He is still not allowed to drive, get married, or vote in a general election, but he is been given a huge responsibility - represent South East London's youth and manage a £25,000 budget.
"It's a great thing to get young people to tell the old people how to do things," says Wilf, excited about his new found empowerment.
Former MP Oona King - who was defeated by George Galloway at the last election - knows what it is like to be a ground-breaker.
She was only the second black woman to enter parliament. And at 29, King was also one of the youngest MPs of the day.
She is convinced that the Lewisham experiment is the start of something much bigger: "It'll only be a matter of time until we see young people being elected around the country in national elections." And that's the key, King says, to getting people interested in politics again.
That corner of London is not new to political experiments. Lewisham is one of the first places in Britain to have a directly elected, US-style town mayor.
Charismatic Mayor Steve Bullock runs Lewisham, but he is worried that he does not represent Lewisham's young people.
"I'm a middle aged, white male - I don't know what it's like to be young in Lewisham today, that's not the life that I lead."
So he created a young counterpart: "It means that I'm hearing voices from a part of the community that I'd otherwise struggle to hear from," he says.
Mayor Bullock (L) with young
mayors and deputy mayors
Bullock had to do something drastic - in his own election, just a quarter of locals voted.
But it is young people, more than any other age group, that are not bothering to vote. Surveys show that just one in ten under 24 year olds vote in local elections.
Bullock's gamble seems to have paid off - the Young Mayoral election got eight thousand under-18s to the polls - that is almost half of Lewisham's young people.
But is it too much power, too much money, for one young man?
The sum of £25,000 is more than most of his friends' parents earn in a year, so what is he going to spend it on? Parties and pizzas for everyone?
Wilf's got loftier ideals: he wants schools to take sports more seriously. And he is promising to give children the opportunity to express themselves through music.
A Young Mayor making promises to his even younger constituents - some of his supporters are as young as 11.
Mayor Bullock sees this politicisation from such an early age as a success: "I hope here in Lewisham, voting has become a way of life," he says.
Oona King thinks there is no alternative: "Without the majority support of the people, slowly but surely you are cutting a government adrift from a democratic mandate - the only way we can change that is to have young people more involved than the adults."
But Wilf's father, Jonathan Petherbridge, was concerned that his son would be used as a guinea pig.
"I was slightly worried to start with. I'm surprised [that he won] and slightly apprehensive, but of course I'm pleased," he says.
Despite his initial reluctance, Jonathan says he will even support his son if he wants to venture into mainstream politics.
"It's a great thing to get young people to tell the old people how to do things"
Young Mayor of Lewisham
But if last year's Young Mayor is anything to go by, Jonathan has nothing to worry about. Manny Hawks is hanging up his political boots at the tender age of 16.
With his hair in a pony-tail, Hawks looks like anything but the archetypal politician. "I've dealt with politics for the last year and a half and it's been really interesting and I've met some brilliant people, but I don't really feel its what I'm there to do," says Manny, "I'm thinking of going into teaching."
The real success of the scheme is not creating the next generation of parliamentarians, but giving young people confidence and ambition. It is about convincing them that they can become tomorrow's teachers, or musicians and sports stars.
Lewisham's 14-year-old mayor may never be prime minister, but as Oona King says: "Democracy is about believing you have the power to change things."