Bullys

Okay, so I have to ask. My 10 year old brother slept over at my house the other night, and in the course of the evening, he confided in Rob and I that he is getting bullied at school, mostly verbably, but there has been one incident where he did get shoved down to the ground. He has told his teacher about it, and even gone to the principles office to report the shoving incident. I guess the teacher doesn't really do anything, and the principle basically told him (and a couple of friends that were there as well that went with him who also get bullied by the same kids) that she's never had those kids in her office before in trouble so she really didn't believe him. Now, keep in mind that this is only my brother's side of the story, but anyone who knows my brother knows that he is greatly concerned with doing the right thing and while he might embelish, like most kids his age, I know something is really going on. He's talked with my parents about it as well, and they really aren't doing anything about it either. I love my parents, but I also know that they are prone to give a lot of advice and tell you how to fix the problem, but they rarely take action, and this is one case where I think an adult needs to be involved. I remember being made fun of at school, and called names, and having issues with other kids on occasion. I think everyone has to learn how to deal with and get along with people we don't always want to. I really believe my brother's situation is different. He said that every recess is miserable. These other kids steal the balls he and his couple of friends play with. They are always swearing at them and calling them names. They constantly threatening him that they are going to beat him up after school. I'm willing to bet it's mostly threats, but to a 10 year old, it can be traumatizing. And, like I said before, there has been one incident where one of the kids actually pushed Thomas and in his words, he "went about 5 feet and fell to the ground." I know Thomas does things that probably don't help, like when they start picking on him or his friends, he threatens that he's going to go tell on them, but at his age, he doesn't know what else to do! Thomas is to the point where he doesn't want to go back to school. He's been off track since Christmas, but will be going back next Tuesday. He's also the type of person to stand up for others who are getting teased or bullied. I know that's actually what caused the shoving incident. One of his other friends was getting teased by one of the bullies, and the bully was bumping up to this other kid like he was going to start fighting, and Thomas went and tried to kind of break it up by getting between the two other kids and the bully ended up shoving Thomas down instead. So my dilema is that I'm not sure what course of action to take. I'm planning on talking to my mom about it, but my fear is that she will try to say that it's not that bad and do nothing. Like I said, I love my mom but I believe that sometimes she turnes a blind eye on things she doesn't know how to deal with because it scares her to go create a "stir" with people she doesn't know. But, I love my brother and don't want him to be traumatized for years to come because nobody was willing to help stand up for him. I think the situation needs to be tactfully assessed, and I think that a little extra attention from an adult during recess would mostly solve the problem. If the "bullies" knew that they were most likely going to get caught being mean during recess, I think they would back off. But, the fact that Thomas and his friends have out right told on them and nothing has happened has probably given them confidence that they can do or say pretty much anything without having to suffer any negative consequence. Anyway, I'm rambling. It has just been bothering me ever since he told me and like I said, I'm not totally sure how to handle it, or if I'm over reacting. What do you think and how would you handle it, knowing that the most obvious first choice would be talking to his parents, but knowing that they might not listen, and even be offended for bringing it up?