This may help with referencing specific skills. It's information from the MAP test which shows different algebra concepts for different RIT levels. If you click the boxes for Math RIT levels 151-160, 181-190, 221-230, and 261-270 you can see the different skills for the different levels under the 2nd major heading "Patterns, Functions, and Algebra."
http://www.powayusd.com/projects/EdTechCentral/lladder/RITScore.asp