Annie123: Thanks for referring her to the Bundles of Love site! I am a volunteer for this organization.
A good baby quilt size is a minimum of 38" by 45". I recently saw a donation of receiving blankets that had two pieces of flannel sewn together at about 30" square. The gal had done a pillowcase turn and then crocheted all along the edges. They were really nice.
If you have a serger, you can cut bibs, receiving blankets, wash mitts, and burp cloths from flannel and then serge the edges. The bibs can have Velcro or snaps on them.
Afghans can be made about 30" square.
You can use any type of material for a hat. Where I volunteer, they make a tam hat with 6 pieces of fabric sewn together with ribbing. When doing baby hats, put both of your hands together in fists and then put them together inside the hat. If they fit, that is a good newborn size.
Thank you for volunteering!
Connie