Would you be able to post his WISC & WJ scores (subtests and index scores) using standard/scaled score and percentile rank? It would be easier to understand the subtest scatter and other patterns that you describe.
The standard deviation for each test is 15. Generally, 2 standard deviations (30 points) is considered significant. Scores can fluctuate, especially when the child is young. Cognition does not always develop evenly across all domains, and this is often reflected in the scores. Patterns of strength and weakness often emerge over time, even if the actual scores change.
It is not surprising me that some of the efficiency scores might be lower given the dysgraphia. One thing to try to tease out is whether or not his processing is an overall weakness, or only something that shows up with a motor component.
This website has good info about both the WISC and WJ cog as well as other tests http://alpha.fdu.edu/~dumont/psychology/
What concerns do you have? Was there testing in any other domains (academic, memory, visual and auditory processing, executive functioning)? What kind of help are you looking for re HS and college? Depending upon what you are looking for, a neuropsychologist may be able to help, but maybe an ed consultant would be better.
