Each designer had a different idea and, therefore, each hat was different. Explain the elements of design. Make sure to include Balance, Form and Color. Demonstrate for the class how to apply these elements in creating a unique design. Discuss the importance of designing your own work and not copying from someone else.
Most designers take pride in their work and deserve proper credit for it.
A bare straw hat for each student. Various different types and colors of material and fabric for the hats. Needles and thread. Feathers, stencils, plastic fruit, lace and any other thing that you feel might be used on a hat. Have various hats on display for the students to see.