National says if it becomes the Government, it will regulate all schools to ban cellphones all day in classrooms and in the playground.
Leader Christopher Luxon says this will lift achievement by eliminating distraction, and enabling students to concentrate on learning.
The Principals' Federation has dismissed the policy, calling it unnecessary and unworkable.
A number of schools around the country have already implemented policies restricting cellphones.
Susie speaks with Matt White is the Principal of Wairarapa College and Ann Brokenshire, Principal of Christchurch's Hillmorton High School, about how it is working in their schools.