(This case study is still in development)

At this young four-year institution, a biology professor teaches "Introduction to biology" (cell biology) to first year students and genetics to somewhat more advanced undergraduates as a blended course.

The class meets two hours a week; students spend four hours a week preparing for class.  What might in some other classes be live lecture is, in this course, homework – a prerecorded lecture with interactive material, readings, writing, and peer critiques online.  This out of class work provides a lot of structure to help students learn to think. 

In their two hours a week of class meetings, the students work on problems.  For example, in genetics class sessions, students work on word problems and critique one another's solutions. These are complex, open-ended problems that require careful analysis and creative thinking. 

So far as the instructor can tell, the students who do the homework can do well in the class. In fact, in genetics lab, some students are working on cloning an actual gene and hope to get a publication in the professional literature.

Simultaneously, however, many other students are not doing much homework.   Instead of doing four hours of preparation for his blended course, some tell the faculty member they are doing perhaps an hour of work a week to prepare for the two hours of class.

Is it because they have been led to expect that homework, class work, quizzes and tests should all closely mirror each other? Some students complain that, for their other classes, they can get high marks while not doing much homework. What might be going on?

What options does this biology professor have, if any, for increasing success rates in this blended course? Or should the prof let well enough alone?