This site has information for putting the RIT value to use:
http://www.wwgschools.org/Northwest%20Evaluation%20Association.htm

For example:

RIT scores between 181 and 190
Whole Numbers
Subtract a 2-digit number from a 3-digit number with a single regrouping
Identify the division facts related to a multiplication fact with one factor as 1,2,3,4,5 and the other factor 0-9


I think this will be useful in advocating for specific differentiated instruction.