I would be intersted to understand the teacher's rational for doing this. I am a teacher, and if children miss homework on a regular basis I set up catch up sessions, first at lunch time, and then after school. When a child gets an after school catch up, a letter goes home first, and the parents are informed of the reason for this.
I only resort to sending a child out of my lesson if their behavior is dangerous or disruptive. They are removed outside for 5 minutes to 'cool off' . I then tell them that they can return, but on the understanding that their behaviour improves. They are told that if it doesn't they will be placed in another class, with a text book and work sheet, and will work in isolation.
Re the computer idea. I do have students with writing problems who use computers. Most of them have just as many problems typing the information as they do writing it. they also find it imposible to draw diagrames etc using the software. When children have problems like this I tend to give them w/s, notes to stick into their books, while the others are making written notes. I then get them to practive the key work vocabulary while they wait for the rest of the class to catch up. Could you sugest something like this to the teacher?
I'd try to have a word with the teacher and get to the bottom of this. It seems like a strange thing to do, a very odd punishment. I don't want to insult your ds in any way, but is anything else going on?
Re the scatty bit. Can he be put on report for homework? That way the staff will check his homework diary and you can get more feed back. Could you set him up with a homework 'buddy'? They could work together, which would help support both their learning.
I hope this gets sorted, Custardo, Kids are such a worry sometimes