This is a wonderful thing you want to do. Yes, you need to be recognized as a Tax exempt entity, and it is a lengthy and involved process. I would talk to your tax preparer or visit www.irs.gov for direction.
Do you belong to a Church? If so, your pastor probably has been through this process and might be very helpful in helping you get started, or may even offer to allow you to start this ministry as part of an outreach of your Church. Best wishes!

