We donate regularly to the RMH and have also stayed there on two different occasions. You picked a very worthy organization to help!!
Ideas for in-room gift bags:
snacks, bottled water, gum, coloring books, crayons, pens/paper, little packs of tissues, toothbrushes, travel shampoo, travel deodorant, travel toothpaste, etc. (some people arrive at the RMH totally unprepared).
If you wanted to go a different route, you could just donate items the RMH. We usually donate things like: cases of water, Clorox wipes, toilet paper, paper towels, trash bags, etc. They also accept travel shampoo, travel toothpaste, etc. Sometimes parents show up in an emergency situation and didn't have time to "pack".
Or, since you have so many amazing volunteers, can you volunteer to cook 2 nights and split the group in 1/2?
Most houses also have a play room, so they accept NEW toys, DVDs, crayons, etc.
So many possibilities!!