Decorations: Use balloons with swirling, bubble like colors.
Food: Bake a cake in a round mold or a metal mixing bowl. Frost it smoothly with white frosting. Save 3 or 4 tablespoons of frosting to color then swirl the different colors of frosting through the white frosting on the cake, the way colors swirl through a bubble.
Serve punch with round ice cubes floating in it.
Make sandwiches of bread cut in circles.
Activities: Give each guest a large plate covered with bubble mix and a straw. Let them practice blowing bubbles then have a bubble contest.
Give prizes for:
The biggest bubble
The highest pile of bubbles
The pretties bubble
The longest lasting bubble
Blowing a bubble inside a bubble
Favors: Bubble gum, jars of bubbles, candy that looks like bubbles, or balloons.
I found this idea in the book Science Wizardry for Kids by Margaret Kenda and Phyllis S. Williams