Escorted by security forces, hundreds of people held a procession through Kumba town in southwest Cameroon, the site of a school attacked by gunmen on Saturday.
At least seven children were killed in the raid according to officials.
People carried placards denouncing the attack, while calling for an end to the violence which has gripped the region since 2017.
"Instead of 6 we have now seven corpses in the mortuary," said Ntou'ou Ndong Chamberlin, the administrative head of Meme division.
"We have to make it stop, they [children] are our future, we need our education, they are our future leaders, violence must stop," said a man at the procession.
The UN called the shooting 'the worst atrocity' since schools reopened in Cameroon two weeks ago.
Fighting between Cameroonian forces and separatist rebels in the English-speaking northwest and southwest regions has killed thousands. Both sides have been accused of committing atrocities.
No group has claimed responsibility for the attack but authorities have put the blame on separatist militia fighters.