Just wondering, what is the job of the person who you wrote to in the district from the website? Writing is a good idea, but I suggest that you make certain that you are writing to a person who has the capacity to help you, and that you make your point short and to the point and something that will get the attention of the right administrator.
Almost every district in the country will have an anti bullying- anti harrasment policy. Many states have laws that will require it, but even if you live in a state that does not, schools that do not have policies are becoming less and less common. First, get back on that district web site, find the email of the superintendent, and ask for the policy and ask for the district complaint policy and step by step procedure. Copy the principal and the teacher. Put "Bullying and Harrasment and District complaint policy" in the subject line. If you cannot email, send a letter. You may even want to deliver all the copies in person. Ask, in writing for the writen policies to be given to you within 10 school days and offer to pay resonable copying fees. Say that you would like a relply from them ASAP indicating that they have recieved your request. If you do not recieve a response that day, repeat the proceedure until you do. I will bet you that it will only take one day for you to have a phone call.
Send a second email to your principal. Request a copy of your son's cumulative file. Again, offer to pay resonable copying costs. Say that you are requesting a copy of any and all personally identifiable information that is in any and all folders and files, from any and all teachers, counselors, diciplinary records, nurse visits; including electronic and paper corespondences between any and all district personel that are about your son. Tell them that you understand that the personally identifable information about other children (especially those involved in Bullying against your son) will be redacted from your sons record. If necessary, offer to come to the school to view the information in person. Tell them that you expect for them to comply with your request within ten school days.
While you wait, make a list of the dates of the bullying, and very short statements about what happend. Try to list the dates that he has had accidents. Call it "decompensation." Make your points short and very to the point. If you contacted anyone in writing and can show that you did so, note that.
If you get a phone call, and you will, tell them that your son has been bullied, that you have tried to get help, and you consider that the school has been deliberately indifferent about your son's distress, and that he has decompensated as a result of their failure to make a safe envioronment for your son. Tell them that you appreciate the phone call, and you have not decided what you are going to do yet, but that you will be waiting for the records and the documents that you requested. If they offer to do something, and you feel comfortable, then you can decide to go forward and send him back to school. What ever the content of the phone call, from here on forward, if you speak to anyone at a school about a serious issue like bullying, do so in writing. A converstaion is worth the paper it is written on, and if everything you have done so far is verbal, it never happend, and you are in a position of arguing that the school "should have known" because you cannot prove that they knew.
I would suggest too, that you contact a mental health professional. Maybe a play therapist, to document his issues and get him some help for his problems, if you are certain that they are caused by stress. I would hold the school responsible, and this is one way to document what has happend and why he has decompensated by having so many accidents.
Be nice, be firm, make your requests, leave all the small details out. Your son was bullied by the following kids...it happend on the following days to the best of your recolection, you tried to get help by speak to the following people, no one at school would help you and you consider them to be deliberatley indifferent about how serious the bullying was, and continurs to be, and that you beleive that your son has decompensated because of the bullying and has begun to wet himself as a result.
Do some research about your state law. This may help you in a great many ways.
I promise you, if you do this, you will not be ignored any longer.
M.