tips for dealing with bullies?

[Guest guest]

My son is shy and a natural follower. He plays with a group of kids where he

likes most of them, but one kid in the group is bullying him and pretty much

only picks on him. I've spoken with the school and they have talked with the

kids but haven't done too much to make it stop. My son can't play with the kids

he likes in that group and still avoid the bully, but when he avoids the group,

he's pretty much alone on the playground. I don't want him to be continually

bullied but I don't want him to lose the good friends in the group he does enjoy

and end up wandering the playground alone. The friends that he has are nice

kids, but not quite mature enough to stick up for him just yet. Any advice?