Until mid-July, her main worry was getting the right grades for medical school.
Now Chilla and her fellow pupils are faced with Turkish accusations that their school has links to a terrorist organisation.
Kharisma Bangsa school is one of hundreds across the world that Turkey wants to shut down because they have links to a US-based cleric, Fethullah Gulen.
The cleric is held responsible by the Ankara government for the failed July coup in which more than 270 people died.
And Turkey argues the schools are part of a strategy to undermine the state.
But pupils, teachers and parents interviewed in several countries say they have no links to suspicious activities.
Turkey looks to close Gulen schools
Who are the Gulenists?
Who is Fethullah Gulen?
Turkey coup: Who was behind Turkey coup attempt?
Kharisma Bangsa is one of nine Indonesian schools Ankara says should be shut down because of their alleged ties to Fethullah Gulen.
Turkey says the schools are part of a vast and secretive network which the Gulen movement has used to build a powerbase and infiltrate state institutions.
Accusations have been levelled against schools with Turkish connections in more than a dozen countries, from Germany to Afghanistan, leaving thousands of children facing uncertainty over their education.
Supporters of the schools say they are no more than a loose affiliation of institutions that share common values and are committed to academic excellence.
From extensive interviews with BBC World Service across 10 countries in three continents, it is clear that the schools have much in common but operate quite differently.
But all are feeling the pressure.
There is no common brand name for the schools.
In Pakistan they are called "Pak-Turk Lycees", in Kyrgyzstan they are known as "Sebat" (Persistence) schools, and in Kenya, "Light Academies".
Most were set up as partnerships between Turkish and local businesses and organisations, but in many countries like Indonesia and Kyrgyzstan, the Turkish partners are no longer directly involved.
Local and Turkish partners say they're admirers of Fethullah Gulen, but not connected to him formally.
"A Gulen school, business or newspaper is generally unofficially labelled as such, because the owner or manager considers Fethullah Gulen as a spiritual leader or source of inspiration," says Turkish academic Bayram Balci.
Alp Aslandogan, who speaks on behalf of Gulen-associated schools in the United States, says there are numerous social networks within the movement. "The schools which are seen as affiliated with the movement were started by people who belong to these networks."
Followers of Fethullah Gulen often refer to their movement by the name Hizmet (service), and the schools all share the same ethics.
"The teachers put emphasis on character-building, morals, and discipline," says Rosi, the mother of a pupil at Kharisma Bangsa.
There's also a strong focus on teaching science.
From Nairobi to Kandahar, school websites show pupils in smart uniforms, studying in well-equipped science labs or computer rooms.
"The children study every day until 3pm, then they have additional classes, activity clubs, and homework," says Baktigul, whose daughter attends a Turkish school in Kyrgyzstan. "At 9pm they all sit down to have tea, and at 10pm it's bedtime."
For Maxim Urazaev, who graduated from a Turkish lycee in the Russian city of Kazan in 2009 the experience was "tougher than being in the army".
Head teachers have told the BBC the schools are not part of a formal structure.
The head of Kyrgyzstan's 21 Sebat schools, Nurlan Kudaberdiev, says they are all connected to Fethullah Gulen informally because the schools were his idea. "But there's no direct influence or financing from his side any more," he insists.
Long before the Turkish government tried to shut the schools down, other countries took action of their own amid suspicion of the network's foreign links.
In 2000, Uzbekistan shut down all Gulen-associated schools operating there, and similar steps were taken in Russia, where only seven remain of the 50 schools that used to operate until 2008. All are now firmly under Education Ministry supervision in the Turkic-speaking Muslim region of Tatarstan.
The schools describe themselves as secular, promoting tolerance and interfaith dialogue.
"In my five years at the school I never once saw a Koran or a Bible," says Maxim Urazaev, from Kazan.
But in Russia and elsewhere schools have been accused of running extra-curricular and secret, religious study groups.
Many former Soviet countries are deeply suspicious of religious activity beyond state control.
A former teacher in Tatarstan rejected the idea of "secret gatherings" but told the BBC that pupils who wanted to could pray with their teachers and talk to them about religion.
In Kenya, former students and teachers showed us books by Fethullah Gulen that they had been given.
In Kyrgyzstan, 15-year-old Zainal said pupils were sometimes shown videos about Islam.
But her mother, Bakhtigul, said she was satisfied it was not a problem. "I even checked the books in their library to see if they had any Gulen literature or suspicious books, but there was nothing."
Gulen-affiliated schools have existed in Turkey since the 1970s and only expanded into a truly global phenomenon in the past 20 years.
That expansion came as Fethullah Gulen grew closer to Recep Tayyip Erdogan, whose Islamist-rooted AK Party swept to victory in 2002.
By teaching Turkish and promoting Turkish culture the schools helped to reinforce Turkey's position and influence across the former Soviet Union, the Far East and into Africa.
In 2015 Turkey invested $6.2bn (Â£4.7bn; â‚¬5.5bn) across Africa.
Somalia became a flagship for Turkish aid and investment, with three Gulen-linked schools catering for more than 1,000 children.
Although the schools are fee-paying and attract the children of the elite, they also offer scholarships to poorer families.
In Pakistan up to a quarter of children are on scholarships, in Afghanistan it is nearly 30%.
Quite apart from the lure of a good education, the schools also offer an opportunity to travel by way of inter-school competitions known as "Olympiads".
Star pupils from Kabul have competed in maths and Turkish-language competitions in Uganda, while children from Mogadishu have tested their skills in Kazakhstan.
The schools say the competitions are a way of making a global network of friends.
But Turkey argues they enable a movement responsible for a deadly coup attempt to continue recruiting new members worldwide.
Thousands of children and their families have been left feeling vulnerable, and for many their future at the Gulen schools is unclear.
"I've been here for eleven years," says Musukan, a sixth former at the Pak-Turk school in Islamabad. "This was the best time of my life. We love it here."
"If Turkey really has problems, don't involve us," says Salwa, an Indonesian sixth former. "We're only here to study and to pursue our dreams."
Jerome Wirawan, Olga Ivshina and Iram Abbasi contributed to this report.
Netherlands
Germany
Turkey
Nigeria
Tanzania
Kenya
Somalia
Iraq
Azerbaijan
Kyrgyzstan
Tajikistan
Afghanistan
Pakistan
Cambodia
Thailand
Indonesia
Russia
Number of Gulen-associated schools: 11
Status: all schools still open, however a Turkish news agency published list of people and organisations in the Netherlands which it said had links to Fetullah Gulen
Number of Gulen-associated schools: 14
Status: all schools still open, however Turkish officials have requested the schools be examined
Number of Gulen-associated schools: 1,032 (plus 15 universities)
Number of students: 135,000 (plus 65,000 in universities)
Status:  all schools and universities shut down. Students allocated to other schools and colleges
Number of Gulen-associated schools: 17 (plus one university)
Number of students: 4,700 (17% on scholarships)
Status: all still open despite Turkish calls to close them. However, they have changed their names to remove any reference to Turkey
Number of Gulen-associated schools: 10
Status: no news of schools being closed, however the Turkish embassy published a letter on its Facebook page calling for the schools to be closed down
Number of Gulen-associated schools: seven (four in Nairobi, two in Mombasa and one in Malindi)
Number of students: 2,000
Status: all schools still open, however Turkey is calling for them to be closed
Number of Gulen-associated schools: three
Number of students: 1,000
Status: all schools shut down after coup and Turkish teachers sent home. Now reopened under new management with Somali teachers
Number of Gulen-associated schools: 37 in Iraqi Kurdistan (includes primary and high schools and a university)
Number of students: 40,000
Status: management of entire network has been replaced following Turkish government request
Number of Gulen-associated schools: 11 (plus one university)
Status: schools taken over by education ministry in 2014. University shut and reopened under new management after July 2016
Number of Gulen-associated schools: 21
Number of students: 12,500
Status: schools still open after government rejects Turkish calls to close them
Number of Gulen-associated schools: 6 schools in 4 main cities
Status: taken over by the government and rebranded Schools for Gifted children in 2015
Number of Gulen-associated schools: 20
Number of students: 8,000 (30% of students on scholarships)
Status: all schools still open, no official call for closure but reports of deep concern from parents
Number of Gulen-associated schools: 28
Number of students: 11,000 (one quarter on scholarships)
Status:  23 Turkish teachers have been removed after Turkish call for schools to be closed
Number of Gulen-associated schools: three (plus one university)
Status: all schools open despite call from Turkish ambassador to Cambodia to shut them down
Number of Gulen-associated schools: four
Number of students: 2,000
Status: all schools still open but Turkish embassy calling for them to close
Number of Gulen-associated schools: nine
Number of students: 2,000
Status: all schools still open after government rejects Turkish call for them to be closed
Number of Gulen-associated schools: seven
Status: schools now operating under Education Ministry management in Tatarstan. Forty three shut down across the country in 2008
"I think it's really sad and wrong they think we're terrorists, because we're not," says Chilla, a bright and articulate sixth-former at the elite Kharisma Bangsa high school near Jakarta, Indonesia's capital.