You can do a theme according to color or according to an idea. Color is easy, get a clear bag, and choose a few items in the same color range, get a nice ribbon, and you have a beautiful shalach monos. Ideas: lunch, coffee break, healthy, or an idea according to what the kids (or adults) dress up as: Monkey- bananas, banana candy etc, yerushalmi – kugel, sunflower seeds etc. Good Luck and have fun.