Waterford is becoming the first county where every primary school will ask parents not give their children smartphones.
A charter will urge parents not to allow their children access to smartphones, social media and age-restricted games, while in school.
It's over mounting concerns around cyberbullying and children becoming inactive by spending too much time on screens.
The Waterford initiative follows on from eight schools in Greystones in Co Wicklow, which recently brought in a no-smartphone code.
Brian Barron, Principal of Portlaw National School in Waterford, says phones are becoming a growing problem.
"All these anecdotes added up to a pattern that we were seeing in our primary schools of children dealing with situations that were way beyond their years.
"The common denominator really was children who were accessing social media, children who had access to their own smartphone, using their own smartphones, and children who were playing age inappropriate video games."