Mobile phones should be banned from primary schools, according to the Scottish Conservatives.
The Tories also called for head teachers to be supported in imposing restrictions in secondaries.
They claim such a move could improve test scores and possibly reduce educational inequality.
The Scottish government said teachers already have powers to ban mobile phones from classrooms and many schools incorporated them into learning.
Officials issued specific guidance on promoting the safe and responsible use of mobile technology in schools in November 2013 - which said a ban would be impractical and unreasonable.
It highlighted positive ways in which technology can "enhance learning and teaching", but also acknowledged there were "risks" associated with young people bring their own mobile devices into schools, including disruption to classes and "more serious misuse such as bullying and harassment".
It concluded that it would be "unreasonable and impractical to attempt to impose a ban on mobile devices in schools", suggesting a "different approach" to promote safe and responsible use while taking a "robust but measured" line on "inappropriate use".
Scottish Conservative MSP Michelle Ballantyne urged the government to overhaul this guidance, calling for an outright ban on phones in primary schools and the introduction of restrictions on their use in secondary schools if head teachers deem it necessary.
The South Scotland MSP highlighted research from academics at the London School of Economics into the impact of banning phones in high schools in England.
It concluded that while phones "could be a useful learning tool if their use is properly structured", a 2013 survey of high schools in Birmingham, Leicester, London and Manchester found that "schools which restrict access to mobiles subsequently experience an improvement in test scores".
The LSE study also found that banning phones "improves outcomes for the low-achieving students the most" while having "no significant impact on high achievers" - suggesting that "banning mobile phones could be a low-cost way for schools to reduce educational inequality".
Ms Ballantyne said: "We are all becoming more and more reliant on smartphones and we know parents see them as valuable to ensure they can keep in contact with their children before and after school.
"But we do need to get the balance right. The evidence suggests that excessive smartphone use in schools can reduce educational attainment, particularly among low achievers. At the same time, we know that online bullying is a growing problem in schools.
"Many primary school teachers would like to see a ban on smartphones, something I support. And in secondary, head teachers who want to restrict the use of smartphones if they think it is necessary should be supported to do so.
"Given the explosion of smartphone use over the last few years, the Scottish government should be looking again at its four-year-old guidance. This may be a cost-free way to help boost standards in classrooms all over Scotland, giving teachers the support they need to deliver the high quality education we all want for pupils."
A spokesman for the Scottish government said: "Head teachers can already ban phones in school if they wish to, however phones are now being used effectively in classrooms to aid learning.
"We encourage local authorities and schools to think carefully about how to incorporate smart and mobile phones into learning and teaching."