A trip to New York that once seemed an impossible dream for three teenage girls from Glasgow is now just days away, and there is still so much to do.

It's Tuesday night after school and their local radio station wants to talk to them. The launch party for their small idea that grew into a big international project is just 24 hours away.

The people from their hometown of Royston are behind them though. A local baker has already offered up trays of cakes and sweets for the party and the money their neighbours' raised for their flights has been banked.

For 13-year-old Hayley Brown and her friends Shelby Johnston, 16, and Michaela Mcphilemy, 14, it is an exciting moment, but it is what comes next that is really holding their focus.

"We're going to document the real lives of real girls around the world," says Hayley. "We want to create the biggest catalogue of girls stories ever told."

With approximately 400 million girls in the world, it is an ambitious goal for the young women who jokingly refer to themselves as just "three wee lassies".

But these are girls who know their statistics, the numbers show that every two seconds a girl under the age of 18 is married and 80% of human traffic victims are female.

These are "three wee lassies" with a plan.

Hayley, Shelby and Michaela are set to travel to an inaugural Girls Club Worldwide Summit in New York in July and together they will interview and film 15 girls from countries including Sierra Leone, Nepal and Mexico.

Each of the girls they interview will then return home and interview 15 other girls from their own area who will all then in turn interview 15 more, with each film being posted on a joint project website and edited into a documentary film on their lives.

"Who better to interview girls than girls?" says Hayley, who says she sees their role as being that of young citizen journalists.

"We're just hoping that a lot of girls across the world will be able to share their experiences on how their life is and on the way they live.

"We know we won't realistically get round all 400 million but why shouldn't we try?"

The summit the girls will attend is made up of partnership girls' clubs in Lower Eastside New York, Chiapas in Mexico, Kathmandu in Nepal, and Kono in Sierra Leone.

In the run-up to the event, girls from the international groups have already submitted short video clips with suggestions of the key issues facing them in their home countries.

"Every girl is different but we all go through the same feelings and can understand what each person is going through even if the situations might be different," says Hayley.

Understanding different situations is something the girls have experience of. The trio belong to the Glasgow Girls Club, a youth led social enterprise that engages teenage girls from under-served areas of the City of Glasgow.

Hayley already dreams of becoming a vet and has carefully chosen her subjects to give her a fighting chance at university. Shelby has recently left school but is fixed on the creative arts.

"Sometimes, when you come from places like Royston, I think people expect you to be nothing more than a statistic, but that's not the case," she says.

"You get the whole 'deprived area' negative box put around you."

Royston, a district in Glasgow once known as Garngad, was one of the worst slums in Europe before a regeneration scheme brought in new housing.

Violent crime in the area, however, remains a strong concern. Just last month, a man was run over and shot in an attempted murder on Royston Road believed to be gang related.

But this is still the same Royston who answered three girls call for help when they asked for a chance to see the world and set their idea in motion.

"When you're from places like this you are surrounded by different extremes of violence and drugs, but I think just being open about it and talking about it helps to overcome it," says Shelby.

"People have been so generous and have really helped us to make this happen."

With the support of the Girls Club, the teenagers have held sponsored car washes and other activities to raise funds for their flights and accommodation to get the project off the ground.

Their filmed documentary is expected to be produced and shown both in film and through a play later in the summer, with support from Glasgow Girls Club founder Amy Rewcastle.

"I am already very proud of what they have achieved," she says. "We are excited to see what stories they bring back."

The girls leave in just a few days time for New York and plan to have the finished documentary edited by the end of July.

"We want to start a conversation about the issues facing girls and keep it going for as long as it takes to get people to listen and help us fight them," says Hayley, who also believes there as many stigmas at home in Scotland to break down as their are challenges internationally.

"I think that people just expect that there is only so far we can go and a limit to what we can achieve," she says.

"We are aiming to reach these really high goals and I feel that sometimes people think that because we come from a certain place or are a certain type of person that we won't be able to do all the things we want in life or become who we want to be."

The club the girls belong to has already received the support of Scotland's First Minister Nicola Sturgeon since they formed three years ago, and the girls believe it is strong female role models who help inspire younger women to achieve their goals.

"I want to go to university and get a job but I feel there are people out there who think I'm in a place where that doesn't happen very often," says Hayley.

"What we want to do is show people that you can be whoever you want to be, no matter where you're from and no matter what kind of life you've lived."

For more information on the project or to find out how to support the girls visit the Girls Club fundraising project site.