When I read the idea for this challenge I was already in the process of developing a new course for our church about water baptism. The whole course is set in a classroom with four students. the instructor, and the person on the computer. I worked to keep the slides, the quizzes, and the feedback slides all on theme. All of it designed to be highly interactive and conversational. Successful completion ends at a printable certificate of completion. I also incorporated Christina Stephenson's suggestion about using JotForm.com as a way of tracking completion. Have to see how that works.
http://openbibleministries.com/03baptsm1.php. Included tips at the beginning of the course on the various choices to navigate the course.