Welcome to the forum mom2one! I agree with St Pauli Girl that it's not straightforward to be able to tell if a child is intellectually gifted based on achievement scores such as WJ-III when that's the only thing you're looking at. These types of achievement tests are made up of relatively short subtests that focus on very specific sets of skills, which is why you'll see large variations in achievement in some children. I also think that tests such as the WJ-III are more likely to be influenced by environment in the very early years of school than ability tests - if a child has been to preschool or been exposed to some basic reading and math skills, they will score much better than a child who's been left to imaginary play all day, even if they have the same IQ.
Another potential gotcha with this type of achievment test, if you see scatter in the scores (like your ds has) - it's helpful to look at what exactly is required on each test - is the question read to the student or does he/she have to read it themselves? Does the student reply verbally or with handwriting? Is the test timed? Sometimes in young children, or in children with disabilities, dips in test scores reflect challenges with those issues rather than actual knowledge.
Re should you advocate for differentiated work for your ds in school? Absolutely! If your child can do the work they're being given easily, if they're getting bored, no matter whether or not they have a "gifted" test score, as a parent you should try your best to get them work that is meaningful and challenging. One of the best bits of advice I've ever had came from a college-aged teen who was working in the playroom where I dropped off my kids when they were little while I worked out. She was a "gifted" book in my hands - one of the usuals, maybe the Davidson's book, I have no idea at this point, but it was when I was stuck advocating for my ds when he was very young in early elementary. The girl asked if I had a gifted child, which makes me uncomfortable - I hadn't meant for anyone to even see the book, I just wanted to read while I was on the treadmill lol. I mumbled something about trying to advocate at school and she gave me the HUGEST pep talk about advocating - she said she and her sister were both gifted and had been bored to tears in school so many times, and that whenever that happened her mom was at school advocating for them - she also added that in their case, it didn't do *much* good (it did help some), but the fact it didn't help wasn't what mattered - what made a lasting impression for her was that her mom was always there, standing up to whoever, advocating for what she needed, and that in turn taught her to stand up for herself
Best wishes,
polarbear
