Amnesty International has investigated on the ground, five airstrikes on schools which took place between August and October 2015.
Five civilians were killed and at least 14 people were injured, including four children.
The Saudi Arabia-led coalition launched a series of unlawful airstrikes on schools being used for educational – not for military – purposes, and the NGO underlines that this goes against international and humanitarian law.
"In the cases that were documented in this report, it was clear from the physical evidence of the strike sites, from witnesses that these schools were not being used for military purposes," Lama Fakih, Senior Crisis Advisor at Amnesty International, who recently returned from Yemen, told RFI.
"There has been other cases in Yemen where some schools have been used as barracks, detention centres and to store weapons. And we do urge not to use schools in this manner because it can render them legitimate military objectives."
She explained that there's an urgent need for all states who supply arms to the Saudi Arabia-led coalition, including the USA and UK, to suspend all supplies of weapons.
In November, Washington approved a $1.29 billion deal to replenish the Saudi air force's arsenal.
Since the conflict escalated, the situation on the ground is dire and many go as far as saying that it could become the next Syria within months.
Social cohesion is falling apart, and for the first time, Shia mosques are being targeted by Sunni extremists.
"It will take at least 10 years for this country to come back to the pre-war situation, economically, and that was not a very good situation already. So what we see of this war, besides many wounded, and at MSF alone we've treated more than 16 000 casualties since the beginning of the conflict in March, and many of them are civilians," Karline Kleijer, Medecins Sans Frontiere's emergency manager for Yemen, told RFI. She said she'd rarely seen such intense conflict.
"But also what we see is that because of the embargo of weapons, fuel is not coming into the country anymore, food is not coming into the country, and this country is 90% dependent on food and fuel coming from imports. The costs of this conflict are incredibly high. Regardless of who will win, or what the peace deal will be, the damage done to this country is huge and it will take years before these people can live together again."
Peace talks are due to begin next Tuesday in Geneva, and most of the important protagonists in the conflict will attend the talks.
The Yemeni government, Houthi rebels and former President Ali Abdullah Saleh will be there and there’s going to be a week-long truce during the UN-backed negotiations.
"I don't think it's likely they'll achieve anything. The fighting is still intense, both parties still believe that they can win this war. The Houtis and former president think that they can regain the territories that were lost in the past few months, and the coalition of the Hadi government still believe they can take back the capital Sanaa," Baraa Shiban, a member of the Yemeni National Dialogue, told RFI.
"What's happening right now, both parties are fighting without any winnings in the fight. And in such cases, you can have intense fighting across the country, but without any clear victory for anyone. I think that if the Hadi government had been able in the past months to secure the city of Taiz, maybe things would have changed, because the other parties would have felt that they'd have to compromise. But at the current pace, I don't think anything will change," he said.
Some analysts have suggested the talks are timely as there appears to be a growing push to defeat the Islamic State armed group - which would better be achieved if all factions unite.
Since March when the conflict escalated, the jihadists have exploited the power vacuum in Yemen.