We went through the same thing in my house. I felt like I was in a race against time too last year when we were figuring out DDs abilities, and how "non-normal" she was. It took 2 things for him to get completely on board with what I was doing. First, I read a James Delisle book, and read parts of it to him, to the point that he actually said, "ok,ok, I'll read the whole thing." The other thing was that he went and picked DD up from kindergarten shortly after she had started splitting her time between kinder and grade 1. She was showing him their work, which was hung in the hall, and the difference between hers and the other kids' work was truly remarkable. He came home saying something like - Ok, I get it now, DD is so far ahead the other kids in her class it is scarey!
I then had his full attention and he got into researching things too a bit, which was a big help.
