Last year we had our first k-5 dance. It was a 70's dance. The kids (and parents) had a great time. We will be picking a different decade for this years dance.
We had a Hawaiin Luau Spring Fling last year. The kids LOVED it!!! We had a WipeOut Splash booth, volcano golf, "Hula" Hoops(b-ball game), and hula lessons to the Lilo & Stitch soundtrack, and more....I was very surprised to see the boys joining in on the hula lessons!! It was a lot of fun. A member got decorations from their employer, which included a tiki hut that was homemade, blow up palm trees and flamigoes, and tropical material for the tables. You could even sell leis really cheap or buy them as a treat for the kids.
Our Spring Fling include a dance, silent auction, bingo, concessions, and sometimes a few other activities. The dance is always a 50's sock hops. Lots of poodle skirts, rolled up jeans, and slicked back hair. Probably only 10-15% of the kids dress up, but it adds to the theme. The kids have a blast.
Ok, Spring brings to mind (at least mine), is flowers, baseball, races, outdoor items, that's all I can think of right now. Hope you get some better answers.