Former physical education teacher Salim Mohamed Nasir has traded in his sports shoes for weighty lesson plans on how to keep at bay the terrorism beast.
Rather than train students to keep fit in body, he now works with young people to keep their minds sharp and their hearts in the right place, so their value systems help them reject extremist views on religion that might lead them astray.
He visits schools, giving talks on terrorism and engaging the young to think of different ways of promoting racial understanding and resolving conflicts.
He was seconded to a think-tank as a research fellow in 2009 from the Education Ministry. Since then, he has held about 60 sessions in schools with over 5,000 students.
The sessions can be a 40-minute school assembly talk, a two-hour talk or a two-day seminar on the topic.
In school, the genial man with a wide smile approaches the topic of terrorism by looking at its historical evolution, its manifestations and solutions.
With younger pupils, he nudges them to speak frankly as the subject itself is sensitive and difficult to comprehend. This gentle reassurance is needed as pupils often cast nervous glances at their teachers seated behind them.
"I tell the children to be brave and that all their questions will be answered," he says.
When he refers to terrorists as nasty bullies, some begin confiding in him, revealing that their classmates are bullying them.
He offers a solution by advising them to fight fear as bullies use fear to intimidate people.
Some of the students' questions are revealing. Some have asked why they must work with children from different races during group work. He urges them not to look at a person's race but accept him as a human being.
Instead of using words like tolerance, which can connote a person's inferiority, he suggests the word "compassion".
"The value of compassion is love, showing empathy and understanding. The need for revenge will no longer be there if there is compassion," he replies.
WITH older students, the tone of discussion changes and they pelt him with tough questions. They discuss topics of brutal deaths, revenge and justice.
In the classroom, two Muslim clerics who are research analysts in the S. Rajaratnam School of International Studies (RSIS) - Ahmad Saiful Rijal Hassan and Nur Irfani Saripi - help out.
Once, when Mr Salim spoke of how it was wrong to use violence to achieve political aims, students retorted swiftly by asking him how then would he justify the controversial US Central Intelligence Agency's drone attacks in Pakistan, Afghanistan and Yemen.
These attacks, argued the students, have killed not just terrorists but unarmed civilians too.
He admits that while foreign policies are meant to protect their own security and sovereignty, some policies are difficult to understand.
Not satisfied with his reply, some retorted that drone strikes can also be seen as an abuse of sovereignty by the Americans and the cause of civilian deaths.
"Sometimes even adults can't answer that question," he admits.
His reply - that terrorists should not resort to terror in the first place - brings the discussion back to the subject of terrorism.
"I tell them two wrongs don't make a right."
Why not seek justice through proper systems and procedures, he asks the students.
His sessions are not just for students but their teachers and principals as well.
To teachers who ask him how social resilience can be built, Mr Salim tells them that it all starts with the individual and how each individual must make the effort to get to know others better.
"If, every day in school, you spend five minutes to talk about these approaches to students, in no time they will not see racial or religious differences. They will see each individual as a unique personality," he concludes.
WHILE he acknowledges that schools are doing a lot to strengthen race relations, his own approach is to provoke and stimulate thought.
When he asks students to rattle off from their mobile phones the names of their five best friends from a different race, the class is silent.
His anecdote resonates with a survey finding this year by the Institute of Policy Studies on the health of race relations in Singapore.
It found that of the 4,131 Singaporeans aged 18 and above surveyed, only 45 per cent said they had a close friend of another race.
But Mr Salim is not unduly worried about the responses on race in his sessions.
"Schools have their own ways of transmitting messages on racial diversity and unity and the awareness levels of students on topics on terrorism are quite high.
"I'm coming in from a different perspective and my questions are meant to trigger thinking."
MR SALIM, 52, is referred to as Cikgu Salim by his colleagues in RSIS, where he is an associate research fellow. Cikgu means teacher in Malay.
He is married to a teacher and the couple have seven children.
His research expertise is on keeping community engagement at the heart of a nation's counter-terrorism efforts.
This year, he co-edited a book, Countering Extremism: Building Social Resilience Through Community Engagement, with RSIS terrorist experts Rohan Gunaratna and Jolene Jerard.
Mr Salim holds two master's degrees. In 2001, he obtained one on educational management from the University of Western Australia. Three years ago, he collected his Master of Science in International Relations at Nanyang Technological University.
For his classroom lessons on terror, Mr Salim draws on his real-life encounters with terrorists and students find this aspect of his work fascinating.
He has been to war zones and even interviewed terrorists in jails overseas.
"Some of them are remorseful but others cling stubbornly to their violent ideologies. They looked at me with suspicion, didn't want to talk and even asked me what right I had to be in their cells," he recalls.
He has also been to Peshawar in Pakistan where he conducted a workshop on how to rehabilitate terrorists. In Yemen, he exchanged views on counter ideology, community engagement and terrorist rehabilitation.
"My world view has changed and I have become a living book.
"Instead of going to a library to read about terrorism, the students get to open and go through the pages of my life," he says.
Last year, Ngee Ann Polytechnic invited him to its campus for a Heroes Seminar where students listened to his thoughts on battling terrorism.
One student wrote in a feedback form after the session: "Mind blown! Really enjoyed the short session behind closed doors."
Another wrote: "A very smart and influential guy. We need more people like him to educate young kids so that they will not go astray."
The cikgu says that as long as the terrorism menace remains, he will wage battle against its extremist ideology and champion mainstream ideology.
"We must reach out to people and share different ways of solving problems.
"We can't keep this knowledge to ourselves. We must share and that is my philosophy," he states.
This is a new weekly series featuring people involved in the fight against terrorism.
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