I'm working through the (PMI approved and PDU supplying) Project Management Professional Series from LearnSmart. I expect most of the approved courses are similar, but these are the specific ones I'm dealing with. If you don't have a copy of the PMBOK, you should get one. (You can download it free if you're a PMI member.)
The first course moved pretty quickly across a wide variety of topics and parallels Chapter 1 of the PMBOK quite closely although with somewhat less detail in some areas. It's interesting to see how the various activities have been corralled and segmented, although there wasn't a lot of information for each in the overview (as expected). It's kind of nice to see it all come together. I had to laugh though - I missed one of the questions on the final quiz. There was a multi-select list of reasons a project might be initiated. The program told me that 'expenditure of resources' wasn't a valid reason for project initiation. Whoever wrote it must never have worked in either a corporation where the budget policy is 'use it or lose it', or a funded start-up where the VCs expect to see forward progress which includes using the provided capital for something other than collecting interest.
This first course uses formal project-management-speak almost exclusively. I don't use a formal vocabulary on a day-to-day basis as I really prefer simpler 'plain English'; however, because I have such a broad (and, um, long) background in project management the terminology used is quite familiar. I understand the need for a common set of terminology for a standards organization and I'm reasonably sure it's going to be important in the certification test. The bottom line here is that if you haven't had a lot of formal project management education you probably want to go through the PMBOK Glossary before you dive into the courses (or at least have it to hand).
Overall it was a good review and a nice framework. I'm pretty sure the big thing here is to manage to memorize the Process Group and Knowledge Area Mapping. Fortunately, there's an appendix in the PMBOK with a lovely chart that should help.