For a grieving child, showing up in class can be an enormous challenge. And if they can manage that, sometimes their grief ca show itself as raging anger. In a split second.
Teachers, do not ever give up on these kids. Instead, listen to them, make them feel safe. Show them that you won't push them away, even though they feel alone and lost. Listen to them, have a conversation. Do not preach about their behaviour.
The fact that orphans show you their emotions, is a great compliment. Because most children only show their true feelings in a place where they feel at home. So don't expell them, don't send them away. Listen. Make a connection.
School may be their only safe place. You *really* do not want to destroy that for them.
Listen. Make them feel at home. Have a conversation. And connect.