At home he should put away his toys and help with little things like setting the table. I know many kindergarten classes now have a fairly demanding programbut there is no evidence that having children do written seatwork at age 5 is of benefit. They are ahead of children who start later but any advantage is erased by the time the children are in grade 4. If anything, the children who start earlier are often at a disadvantage by the time they finish primary they have a poorer attitude toward school because of their negative earlier experiences. Many (but not all) 5 year old boys do not have the fine motor control to complete seatwork, especially compared to their female classmates. When you ask a child with poorer fine motor control to do the same seatwork as a classmate with better fine motor control you are asking him to work much harder than his advantaged classmate. A 5 year old will quickly become discouraged and develop a poorer self image. By the age of 7, in grade 1, he may have caught up. He will certainly find doing seatwork easier.
We actually got an occupational therapist to work with our son, giving him fine motor control exercises, so he would not be too discouraged. The therapist said that one of the problems which she was seeing more often is that children were being asked to do too much, too soon. You can help your child develop his hand muscles through playdough and, if you can find an occupational therapist, she may also be able to give you exercises to do at home with him.
For being the last one done, my daughter was like that. Try to make it a game; we used to see if my daughter could put on her coat or whatever other task we had for her before two minutes were up on the timer. She is better now that she’s older.
I would not worry about the “homework” from school. He should not have any written homework in kindergarten and the negative feelings you’re building up will probobly nullify any academic benefit. If possible, you should be reading to him for 10 minutes per night and that is all. If possible, he may read to you for about 2 to 5 minutes if he is at that stage. If you want to work on fine motor, get him a good Spiderman colouring book and let him colour a page of it. I have been teaching in Ontario for nearly 20 years and have never taught in a school where kindergarten children were given worksheets for homework.

you may not realise this but “ADHD” is NOT a medical condition. there are no symptoms or signs or tests that can be done to prove this.
my mother is a respected doctor, and she told me this herself.
ADHD is just an easy way out of disciplining troubblesome of un attentive children.
i can completely understand that (OBVIOUSLY) this is not your fault.
but the best way to cope with this is to sit him down and talk with him. ask him why he doesnt do his work.
be firm with him and insist that he must do his work.
try and form straergies with him, yourself and his teacher to help him focus.
do not medicate him.. children can be much more effected by the fact they they “arent normal” and no matter how much you try to explain it, he will eventually experiance problems wiht coping wiht the fact that he has to take “medicine”.
imagine the embarrasment on school camps, sleepovers ECT.