What should I do with my savings now that I'm going back to school?

I have $13k in savings and have $9.5k in undergrad student loan debt. I am about to apply for fafsa so I can start my master's program. Should I pay off my undergrad student loan debt with my savings before I apply for fafsa? Will paying off my student debt with my savings qualify me for more grant money through fafsa, given that my expected family contribution is very low? Or should I leave my savings alone? I was saving for a house but if it makes more sense to pay off my debt now and start over saving money, then I'll do that!