Cameroon has started to release some of the 84 children detained for more than six months after a raid on Koranic schools.
The authorities had claimed the schools were being used as fronts for Boko Haram training camps.
Amnesty International says some were as young as five years old.
The release comes after pressure from the human rights group which argued the children were detained without being charged of a crime.
In December 2014, Cameroon said it had dismantled a Boko Haram training camp in Guirvidig near the border with north-eastern Nigeria, and had seized 84 children who were being trained there.
Soldiers captured over 40 trainers and 84 children between the ages of seven and 15, Ministry of Defence spokesman Lieutenant Colonel Didier Badjecks told the Reuters news agency at the time.
He said “many more” had been killed in the raid.
Of the 84 children, 41 have already gone home, while the rest are waiting for the money to get home to their parents, says Amnesty.
Boko Haram launched its insurgency in Nigeria in 2009 to create an Islamic state in the region.
But in the past year it has carried out several cross-border raids in Cameroon.