The law removes distracting internet-connected devices from children's hands while they are at school. High schools will be able to decide individually whether to implement a partial or total ban.
French lawmakers on Monday passed a law banning schoolchildren from having smartphones and other internet-enabled devices at schools.
The ban applies to smartphones, tablets, smartwatches and other connected devices, which must be turned off or left at home.
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There are exceptions for "pedagogical use," extra-circular activities and for disabled pupils, but otherwise the law generally prohibits smartphones in all premises and during school activities outside the school building.
The new rules apply to pupils from three to 15 years old, but allow high schools (Lycées) to decide whether to apply a partial ban or total ban.
A law passed in 2010 already banned smartphone use during class.
French President Emmanuel Macron had promised during his campaign to rid schools of distracting smartphones.
The new law passed with the support of lawmakers from his Republic on the Move! (LREM) party and liberal allies, while lawmakers on the left and right abstained, calling the law "cosmetic."
French students are currently on summer holidays, due to return to school (without their phones) in September.
cw/se (AFP, dpa)