One vendor was asked to custom make a school uniform that was equivalent to an adult's XXL size for a secondary school student.
It may be an extreme case, but uniform providers say they are seeing a general shift towards bigger sizes these days.
Mr Vern Lai, 41, the manager of Johnson Uniform, says that sizes S, M and L were more popular 10 years ago, but sizes L, XL and beyond are in demand now.
His company supplies school uniforms to several pre-schools, primary and secondary schools in the east.
A leading school uniform supplier, Ms Doris Yeo, the managing director of Shanghai School Uniforms, says: "Our children are either becoming too big or too small, and they are no longer of standard size (which is M)."
Mrs Helen Quek, executive director of Bibi & Baba which supplies to a number of top primary and secondary schools here, says that sizes for primary school children "used to finish at size 32 to 34, but it can go up to size 36 now".
She even has to include size 38 for some schools.
She says: "We have to make bigger sizes for secondary school students, especially trousers. We used to stop at 36 inches, but they are going up to 38 and 40 inches now."
And there are students who need sizes beyond the ready-made uniforms, hence the need for custom-made ones.
Mrs Quek says that in a year, she typically receives about 60 orders for custom-made clothes from the more than 40 schools she supplies to.
Similarly, other tailors who offer customised uniforms are reporting an increased demand.
Madam Chong Kuan Yin, 58, owner of Wing Foong Tailoring, says she had at least 15 such orders last year - up about 50 per cent from previous years.
In the same vein, Mr Alan Ng, 45, owner of Chin Hin Tailor, who tailors blazers for prefects, councillors and school performances, says he once saw a Primary 6 boy who was 170cm tall.
He recounts: "He was very skinny but very tall."
Anecdotally, parents are also reporting that their kids are taller and bigger.
Madam Susan Ng Siau Ling's two older children tower over most of their classmates in school.
Her 19-year-old son is 185cm tall, while her 13-year-old daughter is 170cm.
The 43-year-old duty manager says her husband and her are taller than 163cm.
"But my kids are taller than us," she added.
Yet, her daughter is still 5cm shorter than her tallest classmate in class, Madam Ng says.
She attributes the growth spurt to the active lifestyle her children have - both play basketball in school - and their meat-rich diet.
She adds: "All the fast food and (other types of) food that they eat are making them this big."
Madam Zann Puah, 42, a mother of two, says her younger son, who is only 11 years old, is "severely overweight" at 55kg.
The customer service agent adds: "We are trying to bring his weight down by getting him to exercise, such as doing sit-ups at night.
"For dinner, we would give him only two spoonfuls of rice; sometimes when it's too late, we don't give him any rice."
But her efforts have proven futile, she laments.
Madam Puah says her son started putting on weight in Primary One.
"I sent him to an after-school care centre and I think the aunty there fed him a lot.
"The centre served lunch and tea, and my son always got extra helpings."
The liberty to buy his own food in school could have also contributed to the weight gain, she adds.
This article was first published on January 25, 2015.
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