At our monthly Origami Cool Zone workshop, we made waterbomb jack-o’-lanterns and three different bat models.
Dawn suggested the waterbomb pumpkins, which look most pumpkin-like when faces and stems are added! She also suggested the tumbling bat model, which flips end-over-end when it flies.
Brian suggested Nick Robinson’s bat model, and discovered that, when made with 4-inch paper, it looks great wrapped around a tootsie roll!
I contributed one of Stephen Weiss’s flying bat models from his book, Wings and Things: Origami That Flies.
This bat has a long, soaring glide path, and it works best if flown from a high place. Some of the kids figured this out immediately, and stacked a lot of nesting stools and climbed on top to launch their bats.
Kids were standing on all the chairs, and bat gliders were flying all over the place, accompanied by joyous cries of “AWESOME!!!” 
I tried to capture some photos of the flying bats!
Here are some more photos from the Origami Cool Zone:
