My child (8 years old) has a low processing speed compared to all his other scores - a 1 SD difference. This impacts him when he is required to write detailed answers to questions at school and when he is asked to write essays. He says that it took him "too long to think".
I would consider that perhaps what is happening when he is trying to write specific types of assignments isn't related to his processing speed index on the WISC. The WISC subtests require quick visual scanning and fine motor marks, but they aren't asking a student to answer open-ended abstract questions, which is what appears to be the challenge for your ds.
At school, he gets anxious during timed tests where he has to write detailed answers - most commonly in science and literature where there are questions like "why do you think so?" and "what is your opinion or conclusion?".
A few thoughts here - first is: he's 8. It's quite possible that he's just developmentally not quite where his writing ability has caught up with his thinking ability. At 8 in most schools (even in gifted programs) scaffolding is provided around writing assignments *when specific types of writing are expected*, either through graphic organizers or very specific descriptions of what to write. Our kids also had open-ended assignments that were focused on creative writing (story-telling). I volunteered in my ds' 3rd grade classroom during creative writing time where kids were turned loose to write about whatever they wanted to, and some students were able to write easily, others needed quite a bit of help.
I asked him if it was OK for me to ask for accommodations - and he refuses because he is sensitive to being different from other kids.
My ds has a disability and needs accommodations. He also didn't want them in elementary school (and even later on) because he didn't want to look different than anybody else. We were able to get him to use accommodations because we first tried them out at home and he saw that they made it possible for him to do things that previously had been extremely difficult. So if you have an idea, try it out at home. Another thing that worked with us was putting our ds in a situation where he wasn't the only child using the accommodation or where it wasn't obvious he was using an accommodation in a way that was different from other students. For instance, his 4th grade class had alpha-smarts (which I'm sure are so outdated at this point in time no one here would know what they are lol!)... there weren't enough for all of the students, so students could sign up and use them during writing time. The other students didn't know it, but my ds had first priority and could always use an alphasmart whether or not other students were waiting for one.
The thing that's helpful putting together accommodations though is thinking through and understanding what the real issue is.
One thing I'd suggest that might help is to talk him through open-ended questions or rephrase them in a way that isn't as open-ended. For instance:
"why do you think so?" - could be rephrased as "list 3 reasons the bubble burst"
Rather than spend time trying to figure out how to increase processing speed at the moment, I'd focus on spending time at home (or volunteering in school during writing sessions if you can or want too), working with him on what to write. Scaffold for him. Break down his assignments. Talk him through them. Have him use graphic organizers if it helps. If you think the physical act of handwriting is slowing him down let him scribe to you at home and see if it makes a difference.
Last thing I'll note - volunteering in the classroom in 3rd grade really helped me not only in seeing what my ds' challenges were but also in seeing what the level of the other students' writing ability was. It's just a guess on my part so please ignore if you want to, but I'm guessing that your ds is not the only student in his class who is not giving detailed answers to open-ended questions at this point, and that maturity and practice are going to make a difference for him. If this is the case, I'd consider trying to let him know it's ok if he doesn't know what to say for now or can't come up with the fully detailed answer he might be thinking he needs to provide, and see if that helps alleviate his anxiety.
Best wishes,
polarbear
