The problem with DS is that he insists upon doing all of the math in his head. So then he makes careless errors. So teacher is trying to get him to use graph paper for the more complicated problems like (just as an example) 14X60, whereas 8X60 she would let him solve in his head and not show any work.
Yup, sounds just like my DS. Last night he tried to add a string of about 6 two and three digit numbers in his head ... he came close but he made some careless error along the way b/c he was three off... He does the exact same thing and it's to avoid the writing...The fact that he has so much trouble forming the numbers (all of which are reversed, mind you), and it takes so long to form each number, impedes him math and also sucks the enjoyment out of the math. He has done really well doing everything in his head (he got to 4th grade level on Woodcock Johnson applied problems doing all the problem solving in his head refusing to use scratch paper). But, as I keep telling him, he IS NOT a computer - he can't do that forever. He does use graph paper but he just hates the writing. Plus with the inversions and reversals, the writing out can impede the math as well.
Anyway: here is a video of panther math paper. It's awesome:
http://vimeo.com/58327955
