Not to be cruel, but your child threatened another child with bodily harm. What about the child he threatened, how is that child going to cope? It may seem minor but this is how is starts. Actions need to be taken. I understand your son does not know what the full extent of what he was doing but he needs to learn. I would suggest to take your son to counseling. Bulling also needs to be taken seriously and needs repercussions such as no recess, sit in the office or suspension also.
My young daughter pulled a knife on her older sister as well when she was 7 and believe me I played the role reversal and it scared her.

Greatschools does have an anti-bullying group that you might like to join, at community.greatschools.net/groups/11560

I appreciate all your views and advice. I did write a letter to the Principal before I got hold of the letter from the CEO of the NY City Dept. of Education which my son brought home from school. The Principal called me that same morning to thank me for the letter and to inform me of the suspension. I understand that she had to do her job and I even indicated in my letter that I trust the school would do what's best. But I never realized the extent of the punishment until I read the 6-page letter from the CEO. Charges were filed against my son and they listed the "girl" as the witness. Although the witness list is non-binding, it still says something. I know there's no way to dispute the charges because my son did bring the bread knife which he did not take out from his bag while showing it to the girl and telling her he's not kidding. There were 2 charges againts my 6 year old son, (1) threatening prior to the day of (2) possession of a dangerous weapon to wit: a knife. What else is left to do, but to face up to it. What concerns me is, when will the root cause and the real problem of "bullying" be addressed? It is so easy to punish kids who made attempts to stop bullies. What about those who initiated or provoked such incidents? True enough, this has been a learning experience to me and my family. Now, I listen more and talk less.

That is a little extreme to suspend a 6yr old for 5 whole days. Did he kill someone?? really! Well I definitely would write a letter to the principal and superintendent regarding the situation and see if it can be a little more understanding and use a detention in school for 3 days and maybe send child home for 1 to days depending on situation. I know schools have certain rules to follow when a child goes outside of boundaries, but come on 1 week suspension. Dont give up and hopefully something will work out for you.

It sounds like your son's school has a "zero tolerance" policy, so I'm not sure if it would make a difference in the length of the suspension, but you could try to write a letter and bring it to the principal, plus send a copy to the school district superintendent, explaining the situation much as you've explained it to us. You might try to mention that at age 6, your son doesn't read well yet, and obviously never saw the policy book. While you wish he understood it was wrong to scare a classmate to get them to stop taking his things, you might ask if they would reduce the length of the suspension in view of the circumstances.

You sound like a very concerned parent, and it's obvious that you feel badly about what has happened, but try not to dwell on the past. I know it's a bit embarrasing, but if it really is "eating you up" you might even make an appointment with a counselor, or perhaps a minister at your church, who can help you and your son look at the situation with gratitude that nobody got physically hurt, and as a learning experience.

This is such a tough situation and I can tell you feel terrible for not addressing the issue sooner. Obviously your son was not aware of the full repercussions of his actions but you can use this as a learning experience. I think you should just spend the week talking with your son about what happened and why it was wrong and how serious it is to bring a weapon to school and then try to come up with some strategies for both of you to deal with bully situations when they arise in the future.
I remember when I was about seven my older sister was terrorizing me so much that I chased her around the house with a kitchen knife. It completely freaked her out and she told on me. I didn't really understand how dangerous my actions were until my mom got a hold of me!