By Katya Adler
BBC News, Gaza
Thirty hooded gunmen sit at desks around a flip chart, pen and paper in hand, listening to a lecture on the laws of war by the international Red Cross.
The Red Cross believes all parties should know the international laws
All the Palestinian armed factions have signed up to the course, though they are being taught in individual groups.
The head of Gaza operations for the Red Cross, Anthony Dalziel,
said the course was part of his organisation's worldwide effort to teach international humanitarian law to all parties in armed conflict.
"We've taught regular armies and militia groups all over," he said. "Congo, ex-Yugoslavia, Darfur, Colombia."
"We see ourselves as the guardians of international humanitarian law.
"So wherever there are arms carriers, with the ability to influence who is a victim in conflict, these are the people we want to approach, who should know these laws."
Rights and responsibilities
Students are taught basic first aid so they can help injured civilians
Here in Gaza the classes are lively. The teacher is locally-recruited Red Cross staffer Iyad Nasr.
"The guys like to push and to challenge us. They seem to enjoy, to be interested even in the material they are given.
"I can quote one of the guys who said to me, what you are teaching us, this is not the law, this is our life."
Mr Nasr told me how surprised some of the gunmen were to find that groups like theirs have a status under international law.
"But then they also have to realise they have responsibilities. Legal ones. And if they don't keep them, they can be prosecuted under international law.
"And that comes as quite a surprise to these guys, most of whom have always viewed themselves as the victims."
And as freedom fighters, with right on their side.
As the class progresses, bandage wrappers are torn open. The gunmen are given a practical lesson in first aid.
All over the room, masked men pair up to practise, juggling bandages, splints and rescue lifts.
It is an incongruous sight but it sums up the main message of the Red Cross here - it doesn't matter who you are, in times of armed conflict it is your duty to protect civilians, the injured and prisoners.
But will these men change their behaviour outside the classroom?
I asked Abu Hotheifa, one of the gunmen on the course.
"There are things we learned here that surprised us. Things we weren't aware of but as to whether our actions will change on the ground, that is up to our leaders. They decide. Not us."
Civilians are often the victims in the Israeli-Palestinian conflict and in Palestinian in-fighting.
Gunmen use busy streets, even private homes, as battlegrounds.
Armed Palestinian groups fire rockets at Israeli towns like Sderot, just over the Gaza border, almost every day. Sometimes using public areas, like schools, as launch sites.
Abu Khaled is a local factional leader in Gaza. He told me his fighters were told to take the Red Cross course to show the world they are not as many see them.
"People think we are terrorists," he said. "But actually the Islamic law we follow is far stricter than international law in its rules of how to protect civilians and prisoners in war.
"By coming to the courses, we want to prove we are aware of international regulations. In fact, it is the other side which attacks civilians and kills innocent people."
I asked Abu Khaled about the rockets fired at Israel by his faction and others, with the aim of killing ordinary Israelis.
"They are responsible," he insisted. "You can't expect the victims to respect the laws alone. If they stop targeting our civilians, they will see we are open to leaving theirs alone."
Then came a threat not entirely in keeping with the Red Cross class going on around us.
"If they keep hurting our civilians they should know - today we may be targeting their people in Sderot , tomorrow and in the future, with new technology, our resistance will spread further.
"Our missiles will reach deeper inside Israel."
Does Israel think the Red Cross courses will make any difference in the Israeli-Palestinian conflict?
The militants say they are only defending themselves
Mark Regev is a spokesman for the Israeli Foreign Ministry.
"If these groups change their behaviour and stop deliberately targeting civilians, if they stopped kidnapping, stopped shooting rockets in to civilian population centres. If they said 'No more suicide bombings', that would be a significant change.
"Is that about to happen? I'm afraid I'm doubtful."
The Red Cross also teaches Israel's army about the Geneva Conventions.
Both sides in this conflict are accused of breaking international law.
But Palestinian gunmen and Israel's commanders both insist that they respect the rules.
Each blames the other when the fighting gets dirty.