Passing '% Variable %' To SqlDataSource Through E.Command.Parameters

 Hello all,
I'm writing a site with one page that uses the session variable (User ID) to pick one user ID out of a comma separated list in the field Faculty. The default parameterized query designed in the SqlDataSource wizard only returns lines that contain an exact match:
SELECT * FROM tStudents WHERE ([faculty] = @faculty)
The query:
SELECT * FROM tStudents WHERE ([faculty] LIKE '%userID%')
works as I need when I hard code the query with a specific user ID into the SqlDataSource in the aspx page.  It will not work if I leave the @faculty parameter in it:

SELECT * FROM tStudents WHERE ([faculty] LIKE '%@faculty%')
e.Command.Parameters works to replace the @Faculty with a user ID, but again, adding the single quote and percentage sign either causes errors or returns no results.  I've tried several variations of:

        string strEraiderID = "'%" + Session["eRaiderID"].ToString() + "%'";
        e.Command.Parameters["@faculty"].Value = strEraiderID;


no results are returned, not even the lines returned with the default select query.
How do generate the equivalent of SELECT * FROM tStudents WHERE ([faculty] LIKE '%userID%') into the SqlDataSource?
 
Thanks much!