Is he like this at home? Does he throw tantrums and tell you no? If he has this problem at home, school is not going to be able to control him until you get him to behave first.
He needs rules. Children need them to know what is expected of them. They feel safe when you make them follow the rules EVERY TIME.
He is old enough to be able to control his behavior it is YOUR job to teach him the correct behaviors. If he tells you no, tell him to go to his room or the "time out place" in your home until he can find yes. He also needs to have timeouts. Find a place in the house away from everyone that is the "family timeout place". He can sit on the floor facing a wall. This is where he should be sent when he misbehaves so that he can "Calm himself down". He is not allowed to move out of this spot till you allow him to move.If he moves out of this spot, timeout starts all over again.. He can handle 6 minutes in time out. Use a timer so you do not forget.
This should be used when he says no, curses, hits, throws things, whatever is not appropriate behavior, EVERY TIME.
You can also start taking things away from him as punishment. Favorite toys, activities whatever will get his attention. Make him "earn back" these items by rewarding good behavior. Eventually recognizing good behaviors should be happening more than the bad behaviors.
Cursing is NEVER allowed by anyone in the family. If you curse by accident, put yourself in time out. If your husband curses, same thing. Cursing is what people with low vocabularies use to express themselves. Intelligent people have no use for them. We made a list of words to express, surprise, disappointment and frustration.. Following this is easier said than done, but we have to learn to break bad habits.
During a quiet time, you need to have a talk with him about why he yells, hits and throws. He needs to understand he needs to use his words in a good way. He needs to be told what the rules and behaviors at school are supposed to be. Have him write them down or draw pictures of good behaviors..
You need to meet with the teachers and find out what seems to set him off at school. Is he bored? Is he behind on his learning skills? Is he frustrated by something there or at home? Is he getting enough sleep? Does he get enough active playtime, not just watching tv and playing video and computer games.. Some kids do better if they can do their classwork standing up... Maybe you could try this at home with his homework? If he does not finish his classwork, make sure it is sent home each time and that you work on it with him until it is complete.. Does he need to be evaluated by someone with behavior issues? Ask the school to have a observer watch him for a few days.
It takes a lot of work to teach children these behaviors, but they have to at least know how to behave so that then they can sit and learn at school. Do not make excuses for him. He must start to take responsibility for his behaviors. I am sending you strength..