Tara,
If I were to restate your strategy, it seems you have chosen to use the Facebook platform (likely because of popular use from your grads) for the purpose of building/strengthening relationships which is essential to establishing a working alliance that increases the likelihood of collaboration in their job search as well as their willingness to disclose updates to you. This is a good start. Beyond contacting grads for updates, do you use the tool for building/strengthening rapport? If so, how do you do this and how do you use the information you can gather through social platforms to adjust your communication strategies with your target audience? If you currently don't give consideration to this, how might you in the future?
Robert Starks Jr.