It was another Friday afternoon with 19 pupils - but this time, pre-school teacher Lynn Yeo had an extra 20 pairs of eyes watching her.
They belonged to fellow teachers and principals observing her as part of a PAP Community Foundation (PCF) initiative to help teachers hone their skills.
The PCF kindergarten at Tanjong Pagar@Pinnacle where Ms Yeo teaches is one of a growing number of pre-school centres where teachers "do research" on one another's lessons and share expertise.
It was one of five that pioneered the "Lesson Study" technique here in 2009. This has proved so successful that there are now 20 PCF pre-school centres using the method, with five taking it up only this year.
It is believed to be the first time that pre-school teachers in Singapore have been trained in this way.
"I was a bit nervous at first," said Ms Yeo, 21. "But after a while, I focused on the children and it was OK. It helped because they (the teachers) pointed out things about the kids that I wouldn't have seen myself. If I was on my own, I would be running around the classroom."
Ms Magdaline Heng, 46, principal of Tanjong Pagar@Pinnacle, said: "It's like taking a magnifying glass and looking into each lesson to study what works."
A team of teachers meet to discuss the objectives of a lesson. They decide what goes into it, from learning materials to prompting questions to methods that help children keep still.
The classroom is then turned into a "research lab", in which one teacher teaches and the rest observe how the children respond. Each lesson is filmed and takes from 20 minutes to an hour.
The group meets again after the lesson for a review to identify areas for improvement and come up with a revised plan.
Mrs Shirley Ho-Woo, 65, who was behind the idea, was inspired by similar communities in primary schools.
"I saw how effective it was if a school has a culture of collaboration," said the former Cedar Primary principal, who now oversees principals' leadership development at the PCF.
PCF is Singapore's largest pre-school operator, running 353 centres. It is hoping that more will take up the Lesson Study approach, which originated in Japan.
The initiative received funding of about $50,000 from the Education Ministry last year and another $23,950 in June this year. This has gone towards hiring education consultants to help teachers in the learning process, equipping the classroom with materials and holding seminars each year.
"Ultimately, it's the quality of teachers that counts," added Mrs Ho-Woo. "If the teacher improves, then teaching and learning improve. Instead of each teacher thinking in isolation, we can tap the collective wisdom of everyone."