At the start of the term, courses can be cross listed. But as the term progresses and assignments, discussions, quizzes and grades are entered, cross listing is no longer a viable option.
Copy To and Send To
As an instructor, you can use Copy To or Send To as a way to copy or share individual assignments, pages, quizzes and discussions in one course directly into another course in which you are enrolled as an instructor. You can also share material to other instructors at your institution. When you copy or send assignments, pages, quizzes and discussions, any assets within that assignment (images, files, etc.) will be included in your copy.
How to copy to / send to...