Well, I was a left-handed kid when it came to writing, though I did other things with my right hand. For this reason, decision was made to have me switch. And I've had a "disorder in the fine motorics of the right hand" ever since, along with distorted hand-eye coordination and whatever else (including any sort of coordination, basically :p).
I also had dyslexia. The hard kind. Mirror-imaged letters, wrong letter order, utterly awful hand-writing, inconsistent letter shapes, glaring spelling and other errors. But perhaps some of those were a normal thing with a child, I don't know, in fact, I know nothing about the early development of linguistic competence in children. In fact, I couldn't learn to tie my shoe-laces properly (and still haven't been able to :D) and I would confuse the right with the left (which was less fun when I'd confuse west and east during geography lessons and everybody would think I was a lazy uneducated student when I said Greece was in South-Western Europe).
But it also seemed that wherever I had a disability, I also had a parallel talent. It's really strange because while I did have a "challenge" in terms of spelling, I could also easily learn the rules and pick up the practical usage from books I read, to the point my grammar teacher would ask me when she didn't know. And that was when I was 11 or 12 or something like that. I also had a similar talent for grammar and style and the strange-like-heck structures that appeared in my writing when I was a younger kid eventually disappeared. I went on and learnt foreign languages to the point of four at the same time one year, two of them dead. There were awful stumbling blocks but there was also obvious talent, obvious gifts, as if to match.
As for memory, retention and the like, when I was a kid, it was enough for me to read the coursebooks during summer and I could essentially read for pleasure and play computer games for the reast of the year. I was initially the top student, then close to the top, then things took a sour turn, then I actually managed to get below my highschool's average GPA one year, having had flying colours from top to bottom of my early certificates from elementary and then still landing above straight A for several years.
In fact, I'd say most of my problems with grades related to a lack of understanding with the teacher. This was mostly about the method of task solving or presenting the results, or the way a question was framed or the answer was to be framed, although at times I would indeed simply not know the answer to a question. But in most cases the teachers giving me low grades were quirky or had personal problems with me, which messed up the learning and grading process. I had to learn to deal with the blame or shame I considered unmerited. And yeah, I had a lot of wars with teachers, in fact, that's the very reason I was set on my way to become a lawyer. I was lawyering with them at age 10 and now at age 28, I still have nightmares about some of them. And the other kids were a nightmare too.
Where was I... ah, retention. Yeah. Well. Because I was such a "genius", I never learnt to learn the way a normal person does. And this hurt back because later on studying wouldn't work that great for me. With lots of cramming information for an exam, I'd still forget a lot of the stupid little details that would be asked during an exam. Speaking of which, I developed people skills and actually read about communication at a young age to gain an edge in oral examinations. Worked like charm. ;) I once got an A when being surprise-attacked by the literature teacher about a book I hadn't actually read (in highschool, I preferred to sit quietly and read sci-fi books, ignoring the teacher and whatever she went on about ;)). Twice, I think. In law school, I knew that general questions would mean an A. Getting the examiner in any sort of conversation would mean an A unless I messed something up, in which case it'd be B or B+. Detailed grilling would almost certainly lead to a narrow pass and definitely not an A.
There's more but I've already been talking about myself for too long. Right now I'm in the last year of a law Ph.D./SJD programme, working as a freelance professional translator (registered sole-prop) en route to qualifying for official certification and having finished a post-graduate (Master's degree was a prerequisite) study in translation and interpreting. So I basically work with language.