Purposes will vary. Sometimes the purpose may be simply to experiment. While they're creating, they are making decisions about their methods and materials. The students can build on ideas they had before they started, or they can figure something out while they're working that leads them in a new direction. Creating involves finding a way to order colours, lines, textures, shapes, forms and images so that a thought, question, feeling, event, etc. is expressed in visual rather than spoken language.
Evaluation Observe the students while they are working.
Ask the students to tell you what they are doing and why they decided to do it. At the grade one level, their answers will be as basic as the sample statements above. This is fine. It takes time for students to get used to talking about their work. Remember that not all student's process can be used to determine how the student is making decisions about what he or she is doing.