Australian Catholic University senior lecturer Dr Kate Highfield said there was evidence of slight benefits for children who started school older.

“But the data indicates that wears off in a couple of years,” she said.

Highfield said families should consider the circumstances of each child.

“A child developing their executive functions and ability to self-regulate is going to be a stronger predictor of success in school than just age,” she said.

But Highfield said consistency in national rules would support families who moved interstate.

In NSW, a child can start school if they turn five before July 31 of that year. The cut-off is April 30 in the ACT and Victoria, while in the Northern Territory and Queensland the date is June 30.

Alicia Antico’s son Soli was due to start prep in 2024, but she decided to delay his start by one year to give him more time to mature and develop independence.

“Self-regulation is so important, and younger children struggle to pay attention and are more hyperactive, which can lead to frustration in a structured schooling environment,” she said.

Antico said Soli would be five years and eight months old when he started school.

“If I could keep him back again and start when he was almost seven, I would,” she said.

The percentage of prep students aged six by midyear in Queensland surged from 3.93 per cent to 12.45 per cent in the past decade.

According to Education Queensland, parents could delay their child’s entry to prep by one year if they felt their child was not ready to start school, for example if they were still developing social and emotional skills, with no need for principals to sign off.

Loading

A child must be enrolled in school by six years and six months. A Queensland prep classroom can have age differences of up to two years.

Next year, South Australia will tackle the issue of large age gaps and differences in students’ development by introducing a midyear intake for reception students born from May to October.

Students who enter halfway through the year will complete six terms of the first year of schooling.

A Queensland Education department spokeswoman said the eligibility age and cut-off date had been in place since prep was introduced in 2006, and there were no plans for changes in state schools.