Start by including a rainbow and a yellow brick road in your decorations. A rainbow can be made with twisted crepe paper streamers. And the yellow brick road, unless you really make it from bricks, will get destroyed on the ground. Make one on the wall with yellow butcher paper or yellow crepe paper streamers.

Also, cover a pair of slipper with red glitter for a fun centerpiece. It wouldn't be a Wizard of Oz party without red, ruby slippers.

Overall, use lots and lots of green in your decorations.

I’m Going to Get You
Use the popular phrase from the movie: I’m going to get you…and your little dog, too! Come up with alternate things to say. I’m going to get you…and your bowl of ice cream, too! Try it. It’ll be a hoot.

Tornado in a Bottle
Create your own tornado. Give each of your guests a clear (and clean) jar or water bottle that is ¾ full of water, with a teaspoon of liquid dish soap and a teaspoon of vinegar. Add a couple drops of food coloring and a teaspoon of glitter. With the lid on the bottle your guests can swirl around the bottles, or jars, to create their own tornado in a bottle.

Professor Marvel’s Crystal Ball
Have a crystal ball and tell your guests their fortunes. You can use an upside down glass bowl, with some shiny fabric gathered around its base.

Bubbles
Remember how Glenda the Good Witch always shows up in a bubble? Have fun blowing bubbles and maybe let your guests suddenly appear as a good witch, with a wand, through a curtain of bubbles.

Ask the Wizard of Oz 
The wizard is all knowing. This is a twist on a fishing pond game. Let each guests ask the Wizard for something, whatever they wish for most. Then have the guests give a broomstick or a bucket to the Wizard, who is sitting behind a closed curtain. The Wizard will give them something attached to the broom or bucket...probably not the pony that was asked for, but some toy or candy or other prize. 

I’m Melting!
Take turns throwing a bucket full of confetti water on each other. Make the confetti from tissue paper or something similar. You don’t want hard, tiny pieces of plastic getting in your guests’ eyes. Just scoop up the tissue paper confetti and put it back in the bucket. You’re guests will have fun tossing the water, and taking turns melting.

Your family will be talking about your Wizard of Oz party with just as much enthusiasm and fondness in years to come as they do about the movie.