My sixth graders make a pinata for each elementary grade for their
Christmas/Hannukah celebration (we're a very small school - 1 class per
grade). I have the kids divide into groups of approximately 3 each.
They draw sketches of what they'd like to make - not necessarily
Christmas related ideas. All have to be based upon starting with a
large, approx. 12" diameter balloon. They can add whatever they need to
this basic shape.
The tricky part is making the pinata sturdy enough to hold candy (in the
main balloon shape), without making it totally UNbreakable! We use
wallpaper paste with metalyn in it - basically the same as "Ross Art
Paste" - for paste. It saves nicely from week to week without getting
rancid or anything.
We've had some neat results - from a "Minnie Mouse" head to a teddy
bear, from a cactus (using a long skinny balloon to start), to a
dinosaur. Once the first big balloon is dry, you can cut a slit to add
candy, then paper mache over, or cut portions away if you need to add
smaller balloon parts, or other additions. The kids always enjoy it,
and are very proud to contribute to the fun of everyone's party!
Hope this helps!