Your DS sounds very much like my ds. My D's was suspected of having ADD by his 2nd grade teacher but ultimately diagnosed with developmental coordination disorder and dysgraphia. My ds has organizational challenges due to his DCD.
The WISC WJ-III combo will give you a ton of info about how your child learns and strengths and weaknesses but if there are discrepancies in subtests scores or ability vs achievement you'll most likely need additional testing to fully understand what the scores mean and what is causing the discrepancies.
I would write in more detail but my Internet is down and I'm typing on my phone -will come back later with details.
polarbear
