They had taken the children out of the childcare centre for an outdoor activity.
But when it was over and all the kids had returned to class, the teachers accidentally left a two-year-old boy locked outside the centre alone.
Fortunately, a parent spotted the boy and took him to the centre.
The incident, which happened on the morning of Dec 23 last year, upset the boy's parents so much that they withdrew their son from Small Wonder childcare centre in Punggol the next day.
The boy's father, engineer Ernest Lau, 35, said the centre has since acknowledged the incident and apologised to him and his wife.
The centre also said the teachers involved have been counselled on the importance of responsibility and safety procedures.
According to the centre, the boy had been left outside for 10 minutes, said his mother, Mrs Marina Lau.
The 32-year-old engineer told The New Paper yesterday: "If not for the kind parent, the centre wouldn't even have known. He could have wandered onto the road, got kidnapped, or something worse."
Mr Lau said the teachers failed to do a headcount when they brought the children back into the centre after the activity. He related the incident in a post on TNP's Facebook page on Tuesday.
He said: "Their care is a cause for alarm. This is especially so when they can have a child unaccounted (for) and unattended."
He said he was notified of the incident by the school on the same day, but added that the centre did not show him CCTV footage of the incident, even after he had requested it from them.
"The period of time that my son is unaccounted for is not backed by evidence," he said. "The centre is unable to provide me with a satisfactory answer."
According to him, the centre also did not reveal the identity of the parent who found his child, despite his request. He had hoped to find out more about the incident from the parent.
Even though the teachers involved have been counselled, Mr Lau and his wife said they did not feel that sufficient action had been taken.
Their son now attends another childcare centre.
Mrs Lau said: "I do not think this is enough, as it is not the first incident. On Dec 9, my son came back injured, with a cut on his cheek."
She was later told by the teachers that the boy had bumped into a table at the centre and hurt himself.
When TNP went to Small Wonder childcare centre yesterday, the staff declined to comment and referred us to its headquarters. We e-mailed the centre's headquarters, but it did not comment by press time.
The Early Childhood Development Agency (ECDA), which oversees the pre-school sector, said it has responded to Mr Lau's concerns. In a written response, the agency informed him that it has conducted an "unannounced visit to the centre".
The response added that findings had "revealed that there was a lapse in children supervision" and that ECDA would "continue to monitor the centre closely". The agency also issued warning letters to the centre and the teachers involved.
This article was first published on Jan 22, 2015.
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