City College has stopped taking in foreign students since last year, in an effort to keep its programmes affordable.
But the non-profit private school, which prepares students for the O levels, will take in more students this year.
Mr Kenny Low, 39, its director, told The Straits Times that it will not be renewing its EduTrust mark - a requirement to enrol foreigners - which ended in 2013.
The EduTrust scheme sets stringent standards in areas such as academic, financial and administrative processes and student welfare matters.
He said: "These add to the cost of our services, and we want to keep it affordable for students."
He said the school will focus on helping Singaporean students, many of whom have dropped out of secondary schools, or did not do well in their O levels and want a second shot.
"Mixing local and foreign students wasn't so good because there was a language barrier," he said.
"The foreigners couldn't speak English well and couldn't keep up in class. We want our teachers to focus better on teaching."
The school is taking in more students for its preparatory courses - 125 this year, up from 107 last year.
On average, the school rejects 10 to 15 applicants each year, after an entry test in English and mathematics and an interview, which may find applicants more suited to technical courses, or not ready to take the O levels.
Most of the students are between 17 and 19 years old. About 85 per cent of last year's enrolment of 107 were local students. The rest were mainly foreign students who enrolled two years ago.
Students pay $4,500 to $5,600 for the school's one-year programme, depending on the number of subjects they take. The school gave bursaries to 20 students last year.
Its students have performed better than private candidates nationwide in the last few years, with the exception of 2012.
In 2013, for instance, the school achieved a 92.7 per cent pass in at least one subject, better than the national average for private candidates of 90.3 per cent.
Close to 60 per cent of its students qualify for institutions such as local polytechnics or junior colleges. Some opt for private diploma programmes here or overseas.
The school, which rents a space in the Wisma Alsagoff building in North Bridge Road, was formerly known as CHEC, or City Harvest Education Centre.
Set up by voluntary welfare organisation City Harvest Community Services Association, the social service arm of City Harvest Church, the school started with 20 students at its Suntec City premises in 2002.
It was registered as a non-profit organisation in 2005, and renamed City College in 2009.
It receives funding from City Harvest Church yearly to subsidise school fees for students.
Mr Low said its teachers are encouraged to be more creative in class. "Our students tend to be a bit more mature, having had some experience," he said. "They don't start from zero."
So teachers adopt an interactive approach. Mr Low, who also teaches physics in the school, said: "We give them opportunities to demonstrate knowledge instead of just listening. So students may finish a quiz or do an experiment before the teaching begins."
Sandra Kho, a student who retook the O levels at the school last year, said "speed dating" was a typical method teachers used in class.
Pairs of students would sit across each other, and test their peers in chemistry, physics and geography, with the help of questions and
answers on cards prepared by teachers.
"It was fun and it helped us remember the facts," said Sandra, who first sat the O levels at Bukit View Secondary in 2013.
"I couldn't get into polytechnic with my results. I wanted to challenge myself to do better. I did study but I think it wasn't enough," she said.
"This time, I did more revision after every lesson and I made sure I didn't make the same mistakes," said the 18-year-old who hopes to be a kindergarten teacher.
This article was first published on Jan 14, 2015.
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