I'm curious about the "new playable area" wording, and would like to hear more. Would I be correct to surmise that the reason we're moving from Pendor to Amala and effectively working off a new mod framework is so the students have the experience of creating and balancing and fine-tuning a new gameworld from the ground up? Loosen the bonds to the already-existing modding philosophies and all that?
Does 4.0 mean that the final iteration of 3.x is a finished product? Could you foresee tying the new and old gameworlds together in some creative way? As in, complete a set of goals in Amala and then hop on board a ship to the brave future of our present Pendorian gameworld for innovative hard-mode challenges yet unforeseen? Or is that story finished?
And will we of the Taleworlds community have the chance to interact with your students? Useful skill for them to develop, and we're a friendly bunch. 
Interesting question: The current 3.31 is "finished" and I have no plans to add new features to it, or to spend additional time for fine tuning balance at this moment.
Can I foresee tying the two game worlds together? They are tied together, just not physically. POP 4.0 starts up at the end of the game of 3.31, after it has been "won".
There are real technical limitations in terms of game resources that would prohibit the merging of the two offerings into one game. We are already seeing POP 3.31 busting at the seams due to the amount of game resources loaded: and we match that for 4.0.
Besides this, the time lines do not match. POP 4.0 is set a generation or so beyond the end of POP 3.31.
The students of this program are receiving the experience of what it is like to work in a multi-cultural distributed development environment. They are not full time employees, but spending 12 to 20 hours a week working on this depending on their "role" on the team.
They are facing the same problems that any game development team does, and are working through them as we go. This is a very challenging experience for them especially when working with our regular team members who are past "school" and well into the real world with their respective careers, levels of expected performance and acquired expertise.
Best regards,
Saxondragon