Skateistan, Kabul's first skateboarding school, is perhaps the most unlikely non-profit sporting organisation in Afghanistan.
The charity, which combines skating with education for street children, says its priority now is to continue working after a suicide bombing that left four of its students dead.
"This tragic incident will not deter Skateistan from continuing our activities in Kabul," media officer Rhianon Bader told the BBC.
"We have many street working kids coming each week, and this incident only makes it more clear how important it is that we provide them with a safe space to have fun and gain access to education.
"More than the despair we are experiencing, we know that keeping the skate park open remains a light in the dark for the children here."
Those killed in the attack by a teenage Taliban bomber included Nawab, 17, and Khorshid, 14, who were instructors at Skateistan.
Khorshid's sister Parwana, eight, and student Mohammad Eesa, 13, also died, as did Assad - Khorshid and Parwan's cousin. Navid, a 14-year-old volunteer, is in hospital, seriously injured.
They were a tight-knit group, hawking scarves and chewing gum on the streets of the Afghan capital one day, donning helmets and kneecaps and gliding down skating ramps the next.
It's the second time the charity has been directly affected by the conflict in Afghanistan which has claimed hundreds of young lives in recent years.
Last December, four former female students were killed in a suicide attack targeting Ashura religious celebrations. Four of the charity's current students who were begging in the area were seriously injured.
Skateistan was started in 2007 with 10 skateboards by Oliver Percovich, an Australian now aged 37, who had moved to Kabul with his girlfriend.
He recalls how many kids shrieked in excitement when they saw him skateboarding. Some of them boldly came forward to borrow his skateboards. And when those boards came back to him in tatters after a few days, his decision was made.
"These kids are trying to break the shackles of old mentalities in Kabul. They are not scared. If they hadn't come after me every day, I would've left a long time ago," he told the BBC two days before Saturday's bombing.
Mr Percovich was unavailable for comment after the attack.
Afghanistan has some of the toughest conditions in the world for children, with many working on the streets selling scarves, trinkets and chewing gum.
Skateistan started small, offering daily practice sessions in public spaces in Kabul. Street kids went along, as did children from richer families and it was a chance to bring them together, organisers say. Soon it was time to take the next obvious step: to build a skate park.
Mr Percovich admits that, at the beginning, he struggled to get by on only $10 a day. But eventually, donations started to flow in and he managed to get help from the Danish and Norwegian embassies.
Companies like Black Box Distribution contributed skateboarding equipment. The final step was persuading the Afghan Olympic Committee to donate land to set up the park.
The charity, whose logo is an assault rifle snapped in half by a skateboarder's wheels, hopes to open a new facility in the northern city of Mazar-e-Sharif later this year.
Today, nearly 400 children take part in Skateistan, 40% of whom are girls - making it the largest female sporting federation in the country.
In conservative Afghanistan, girls cannot be seen associating with men in public after they hit adolescence.
Recruiting girl students into Skateistan is a detailed and complicated process, says the charity's education co-ordinator, Benafsha Tasmim, 23.
"Parents allow girls on a number of conditions, the most important of which is that they practice in a female-only environment. We have classes for boys and girls separately."
Employing female instructors like Khorshid who died in the bombing helped in solving the problem.
One organiser says Khorshid was "always smiling no matter what troubles she had to deal with every day. She knew what she wanted in life and wasn't afraid to fight for it despite having more responsibilities and sorrows than a child should ever have."
The school will conduct memorial services throughout the week, providing assistance to families who lost their children in the attack.