My son has some similar issues and he also much prefers to read, act, write, sing, do social studies and science than do math. He tells me that he thinks math is boring but useful so I just think for mine it is a lack of interest. It can't be a memory thing with him because he can do things like memorize my credit card number and other numbers easily. He could usually remember all the steps to solving problems and often came up with ways to solve the problem differently using as little writing as possible or doing the problem mentally because of his dysgraphia.
It almost looks like he has ADD when he does math sometimes but he doesn't have it for anything else. I got him to practice math computation this year by having him do 8th grade math on IXL and using mostly mental math or letting him solve the problems any way he could just so long as he got the right answer. IXL takes away points if you get an answer wrong which I really like because it forces him to pay closer attention to computation while also increasing his speed. I told him that some of those approximately 250 8th grade math skills are what I have found most useful in every day life but I had forgotten some of it and had to relearn it. We plan to use IXL or something like it to practice math even as he takes higher level math to keep those skills sharp.
But still, there are days, even with practice, when he makes computation errors and it seems to be just some kind of glitch that happens. It makes him mad when he makes errors on easy things and sometimes refuses to do any more math that day. He is more likely to make a mistake on something easy than on something harder for some reason.
