So, I sifted through all the resources I could find, and after one big headache, boiled it down what I think is the latest and greatest thinking on the subject, and included the categories that made the most sense for students: Independent, Dependent, Relative, Nonrestrictive, and Restrictive. Although I looked at a plethora of sources, the one that most informed my choices was from the online library at the University of Phoenix.
This power point is a great starting point for clearing up clause confusion. It has explanations and clear examples. I used it in my classroom this quarter, and the test scores on the subject confirmed that it helped. I hope you will find it helpful, also.
Ho, ho, ho!