Dottie, thank you so much for the quick and extensive reply. I must say you're probably holding a crystal ball because your estimates correspond with "test age equivalent" that we did get for each raw score:

Chronological age is 7:5.

WISC-IV
Raw Scores/ Test Age Equivalent
Similarities 17 9:2
Vocabulary 33 10:2
Comprehension 13 6:10
Block design 48 14:10 (yes, definitely a spike!)
Picture concepts 13 7:6
Matrix reasoning 19 9:2
Digit span 12 7:2
Letter-number sequencing 12 7:6
Coding 57 Above 7:10 (reached ceiling, apparently)
Symbol search 41 Above 7:10 (reached ceiling, apparently)

Composite Scores
Verbal comprehension 112
Perceptual reasoning 121
Working memory 99
Processing speed 131
FSIQ 121


WIAT-II
Raw Scores/Test Grade Equivalent
Reading 48 3:3
Mathematics 38 2:9
Language 41 4:2
Writing 31 2:9[i][/i]

Do you have any idea what a spike in block design means in practical terms? My husband and I believe we are already addressing our son's academic needs with the third grade curriculum, but we're concerned that we might need to supplement the block design aspect because of the unusual score. That and the high processing speed-low working memory discrepancy.

P.S.
Thank you so much for computing the GAI. We thought it would be lower, which goes to show how much we don't know about this test. Thanks again. smile