Many teachers are not provided with computers to use outside the classroom for lesson planning, and the NSW Department of Education does not know how many schools have implemented a Bring Your Own Device scheme for students or how many teachers have devices, the report says.

The report also warns that the department is "not sufficiently monitoring the digital literacy of NSW students, which has declined in national tests".

About half of all the computers in schools are at least five years old and about one in eight are from the last year of the Commonwealth's Digital Education Revolution program, which provided laptops for year 9 students from 2009 to 2013.

"The department's vision to enable 'any learning opportunity, anywhere, anytime' is at risk of not being fully achieved due to accelerating demands placed on ageing devices and school wireless networks," the report says.

The main program that has delivered computers, devices and servers since 2004, Technology for Learning, provides one device for every eight students, and last year the program provided each school, on average, with $23 per student, which can be spent on desktops, monitors and notebooks for teachers and students.

"Annual funding of $35.3 million has not increased since 2004, despite a 3.6 per cent increase in the student population in this time, and an overall greater emphasis on using information and communications technology (ICT) in the classroom in policy and practice," the report says.

As a result, schools have to supplement funding from general school budgets and contributions from Parent & Citizens Associations, according to the report.

The report said a 2016 survey of teachers showed high school students in lower socio-economic areas had fewer opportunities to use technology compared to those in higher socio-economic areas.

Many school wireless networks also do not have the capacity to deal with "current and future needs", making it difficult for students to effectively use portable devices.

"Increasing use of technology by teachers and students through Bring Your Own Device schemes and cloud software is placing greater demands on legacy networks," the report says.

President of the NSW Secondary Principals' Council, Chris Presland, said one of the biggest problems facing schools was a lack of dedicated IT support specialists.

"Often all a school will have is an interested staff member who offers to run their network and they are given some teaching periods off to do that," Mr Presland said.

Mr Presland said teachers also needed more professional development to keep up with fast-changing technology.

A statement from the education department said: "The NSW government's $46 million Connecting Country Schools program will boost wireless access and internet capacity in 13,000 learning spaces in around 900 regional schools.

"The department is exploring the program's expansion to urban areas to provide ongoing enhancement of wireless networks in all schools."