Scope and Sequence over multiple grades

For the first time I am teaching two courses in which I will teach about the Holocaust. You're probably thinking how great this must be. I'm thinking how complicated this could be. The complication arises from the fact that the 10^th grade Advanced Studies World History class is a feeder class for IB History. So in 12^th grade I will probably have many of these same students. For years I have taught the Holocaust to just the 12^th grade IB History students. For this group I avoid teaching a general history of the Holocaust. Instead I tend to focus on a few specific topics as well as let their questions dictate some of the lesson planning. My assumption has been that these students have been taught the general history of the Holocaust in earlier grades.

With my 10^th grade Advanced Studies World History students I have the opportunity to spend a significant amount of time (maybe a whole 2 weeks!) teaching the Holocaust. This means that I will most likely touch on some of the same topics as the 12^th grade IB History students cover. I'm struggling with how to approach these topics. The dilemma is how to teach these topics in 10^th grade then vary the lessons enough in 12^th grade so as not to turn them off to the study of the Holocaust. For the first step I will be surveying my 10^th graders about what they know (or think they know) and what they have been taught about the Holocaust. Hopefully that will give me the direction that I need to plan the lessons.