In reply to J.S.F..

Welcome to SAS! I think you want to use the BY statement. Almost every SAS procedure has a BY statement, including SGRENDER. If you have a variable called GRADE with the values 6,7,...,10, use PROC SORT to sort the data BY GRADE. Then in the SGRENDER procedure, include the statement
BY GRADE;

Since you are new, let me tell you about the SAS support communities. These are places for anyone to discuss "how do I do..." in SAS. There is a community for "SAS/GRAPH and ODS Graphics" that can help you with additional questions like this. There are also other forums on the DATA step, statistical procedures, and so forth. Enjoy!