I find it very difficult to teach art. In a recent search, I came across an art teacher's blog that is terrific for a person such as myself. The author writes clear descriptions and posts pictures to help you through the creation process. Encouraged by my spouse, who tells me that the only way to teach art to students is to do it yourself, I painted a "Paul Klee Inspired Heart Painting" on my own the previous weekend. After my students learned about Paul Klee and we discussed some of his artwork, I then walked my students through the project this week, step by step. They loved it. At parent teacher conferences last night they proudly showed off their work.
If you struggle with teaching art, check out A Faithful Attempt. There might be a project or two that you can use for your class.