Member retention specifically juniors

Hi everyone, I just got a new position in my sorority and am stumped for ideas when it comes to member retention. Ive researched it a lot and have seen ideas about surveys (we already do that), random and anonymous retention committees (I don't think my chapter would do this), weekly events (we do this), and so forth. I know girls are going to drop, but they all do it junior year because they've checked out. Freshman get bigs, Sophmores get a little, and Seniors get all the grad stuff. But girls in my chapter complain "juniors get nothing" which isn't true, but I agree junior year can be less exciting. Any help or thoughts would be appreciated!