The first Pat's Schoolhouse, set up in Whitley Road in 1988, was built on a promise to deliver top-notch early childhood education.
In an era when the sector was staffed mostly by O- and A-level certificate holders with little formal training, its founder, Mrs Patricia Koh, wanted more: She insisted on hiring graduate teachers to deliver that promise.
She had left her "cushy job" of 10 years at the National Institute of Education's pre-primary department, feeling that the biggest difference in education began with a child's foundational years. "I wanted to create a happy school environment where children do not fear getting things wrong," she said.
Within a year, the first pre-school was full, and it soon had a waiting list of up to two years. That passion drove the brand - now synonymous with premium fees, strong pedagogy and bilingual classes - to the upper end of its ilk.
At the time, it could command about $300 a month for three-hour programmes, when government- linked pre-schools charged between $12 and $50.
Today, the chain has 18 branches and two infant care centres. The latest outlet will open for previews on Sept 24 in Sembawang. Monthly fees of about $1,800 for full-day programmes rank it alongside Brighton Montessori - ahead of the $700 to $1,100 charged by other centres such as Cherie Hearts, but lower than the $2,000 to more than $3,000 charged at the likes of Avondale Grammar School, EtonHouse and One World International School.
The good news? The waiting list is down to nine months.
The 65-year-old - a mother of three and grandmother of five - began teaching at 17. She calls Pat's Schoolhouse her "first child", and sold the chain in 2007, then with 12 centres, hoping to see it grow overseas, even in the United States.
Its buyer, global education group Knowledge Universe (KU), doubled her last best offer, she said, though she declined to reveal the amount. KU promised to support her as she fronted Pat's Schoolhouse, but when that fell through, she left the group in 2012.
That lesson learnt, she is going about things differently. Now chief executive of her second chain, three-year-old MapleBear Singapore, she oversees its 14 pre-schools, with a 15th opening next month.
Also next month, she will launch MapleBear in Manila, adapting her template to teach teachers in the Philippine city to capitalise on the strengths of their inherent musical culture while incorporating stronger pedagogical techniques. From November, Mrs Koh plans to evolve other centres in Hong Kong and Shenzhen in a similar vein.
"We will take it step by step and find the right opportunities with the right partners," she said, adding that she still intends to reach the US, Australia and England, but is unlikely to sell her chain again. "I want to grow, but with me in charge all the time."
The one-time teacher at now-defunct Silat Primary School still gets most excited interacting with children. During this interview at the MapleBear Horse City centre, she stopped a few times to engage the children as they showed her their collages, and to speak to parents as they came and went.
Not keen on retirement, she is working towards leaving a legacy of having taught teachers so well that as a result, "we've made a difference in the life of children".
"Work is not work to me," she said. "Looking at the face of a child, hearing them call you and hug you, that's what delights me."