Outlines of James tend to swivel between hopelessly complicated or forced structures on the one hand and frustrated resignation at the prospect of discerning any structure at all on the other. Carson and Moo suggest what in my mind is a nice middle way, and believable. Within the broader compass of a formal letter (with opening, body, and conclusion), they suggest four sections:
1. Trials and Christian maturity (1:1-18)
2. True Christianity seen in its works (1:19-2:26)
3. Dissensions within the community (3:1-4:12)
4. Implications of a Christian worldview (4:13-5:11)
A sensible break-up if one wanted to teach a four-part Sunday School lesson or preach 8 to 10 sermons, but not much more, on the letter.
--D. A. Carson and Douglas J. Moo, Introduction to the New Testament (2d ed.; Zondervan 2005), 620-21