Hi, so if I am reading this correctly he already had WPPSI done and some of his scores are >150?
To get an idea of his decoding level you can look online for http://rrf.org.uk/burtinstructions.htmlhttp://rrf.org.uk/burtinstructions.html
or
http://www.readingkey.com/tests/readinglevel/readingtest.html I "knew" that my dd would have no problem with at least the reading part of the achievement test since she was reading (for pleasure) books that were 6+ years ahead of her grade level.
If you already have the WPPSI, you could apply with that and the portfolio. If they need something else, they would let you know.
Good luck!
