Hi Juliet,
 
Perhaps your child is having some difficulties with his fine-motor control.
 
 Does he find it difficult to print the letters evenly?  Are they different sizes?
 
Is he having difficulty forming the letters with the same motions each time?  Does he sometimes use left-right, top-down motions, and sometimes use backward and reversed motions?
 
Does he forget what the letters look like?
 
Does he sometimes make reversed letters, e.g. printing "b" for "d".
 
If you notice that your child is having any of these difficulties, perhaps he doesn't like to print because it's hard for him.
 
You could ask for an assessment by an occupational therapist, to see if your child's fine-motor control is developing satisfactorily.  If he's developing slowly in this area, then the occupational therapist can give you fun exercises which will develop his hand control.
 
Until you get this assessment and this assistance, I would suggest that you make the job of printing easier for your son.  For example, have him copy some of his material, but not all of it.  You and he can decide ahead of time how much he'll copy, then when he's done he'll feel satisfied because he accomplished something.  You could reward him for the number of letters and numbers he prints with his best work.  He could work toward increasing the number that he can print neatly.  You could make a chart indicating the date and the number of letters printed, and he could watch his skills grow.
 
Let him have a letter/number line at his workspace, at home and at school, so that he can refer to the shapes as he's working.
 
Make certain that this letter/number line has arrows and red/green dots, showing where to start each letter/number and which direction to move his pencil.
 
If he needs to spell some words, you could have him tell you the spelling of some of them out loud, and some of them he could print.
 
If he's writing a story, you could print, for example, the main part of the story, and he could print the beginning and the ending.
 
I usually find that if we give children some choices, they want to improve their skills.  Your son may be feeling overwhelmed by the quantity of printed work that he's being asked to do.
 
 
Sincerely,
 
Sylvia HS
Reading Specialist
Author