Could someone help me with these KTEA-3 Brief Scores?

Composite
Standard Score
Description
Reading 127 Above Average
Math 122 Above Average
Writing 100 Average

Subtests
Letter & Word Recognition 123 Above average
Reading Comprehension 126 Above average
Math Computation 116 Above average
Math Concepts & Applications 125 Above average
Written Expression 97 Average
Spelling 100 Average

Child (my 14 year old son) has an IEP for specific learning disability in Written Expressions and I fear the school may push to take away IEP based on these scores. Not sure how he scored average in writing when he can not handwrite to save his life.