An exclusive group of paddlers from Great Britain, all named "Nigel", who won't let Americans hold their coveted 5-star rating. Just kidding.
The BCA is a "governing" body for British Paddlesport. As such, it is highly obsessed with paper qualifications and coaching, and more of its work is concerned with competition than with wilderness paddling. That's not to say that it doesn't try to represent wilderness paddlers, but that many such paddlers find its culture rather alienating.
The BCU system has two development tracks, one for paddling proficiency and one for teaching
The novice paddling level is One Star, progressing up to the Five Star or expert level. Participants are coached and then tested at each level.
Similarly, the teaching awards go from Coach 2 through Coach 5?
Here is an article from the Chesapeake Paddlers Association on the Atlantic Kayak Tours web site about their experiences with BCU methods. http://members.aol.com/KayakTours/BCU.html
Note that "canoe" in Great Britain means the same thing as "kayak" in North America. "Canoe" has traditionally been used interchangeably in Britain for canoes and kayaks, although nowadays many more people make the distinction.