Students have returned to class minus a major distraction, as a mobile phone ban in NSW high schools comes into effect.
The state's public high schools joined government primary schools in enforcing a ban on mobile phones during school hours when term four began on Monday.
Victoria, Tasmania, South Australia, the Northern Territory and Western Australia already have bans in place, while Queensland students will face one from next year.
The ACT is consulting its residents about a possible ban.
Education Minister Prue Car said each school was choosing how best to apply the key election commitment from Labor.
An off-and-away policy in a lot of schools requires phones to be left in students' bags or lockers, while other schools have lockable pouches or phone lockers introduced for the change.
"Here at Ashfield (Boys High School) there are lockers in every roll call class, so that boys can put their phones away, take a card and then collect them at the end of the day," the acting premier told reporters.
"We have done this ... to make sure that we can improve the focus and concentration of our young people in front of our wonderful teachers.
"This will also mean that at recess and lunch, they might actually be running around playing with each other, interacting, talking ... actually socialising."
The introduction of the statewide ban coincides with the introduction of a substantial increase in teacher salaries, making new graduates the best-paid in the nation.
"(The phone ban) is just one of the mechanisms we're using to improve the educational outcomes across the state, like increasing teachers' pay, giving more admin support to teachers and ensuring that schools are fully funded," Ms Car said.
The government has cited UK research indicating improved educational outcomes from phone bans and will evaluate the effect of its own policy.
But mental health researchers Black Dog Institute said there was little evidence to support phone bans to raise student performance.
"The evidence around the effects of banning phones at schools on academic outcomes is probably more mixed than the government would like to admit," the institute's head of population research, Aliza Werner-Seidler said.
The policy affects 320,000 students in 400 public schools.
Each school decided how to implement the ban, with some exceptions for students who need their phone for health reasons, such as to monitor blood sugar if they have diabetes.
