Sounds awesome!
What about that old game where you drop cothespins into a jar, but make them look like fingers? Make the jar look like a head and the opening a mouth?
For a fast, fun treat, put large marshmallows on popsicle or lollipop sticks and then use icing to glue on m&m's for the pupil and food color for the iris and for veins to make the eyeballs look boodshot. Use a toothpick dipped into red icing for the veins.
I will post other ideas later. I adore Halloween and have tons of ideas/books on crafts/foods for parties etc...