@LinHua
You could try the following "trick" to see if it works out for you --
1) Remove all student enrollments from the previous course -- you'll need to do this or you won't be able to progress to step 2
2) Mark the course as a blueprint. You can do this through the API or by going through each course and checking the box that marks it as a blueprint course.
Also ensure that at this point each course has a SIS ID -- you'll need it for the CSVs. I usually use bp_ followed by the course ID
3) Download a CSV of the courses for your current term
4) In the column for blueprint_course_id, put in the SIS ID of the course you want to copy.
5) Run the file, it should sync the course as a blueprint, with all the associated materials.
6) Re-run the CSV of the courses for the current term but instead add "disassociate" in the blueprint_course_id to dissociate the blueprint.
It's a "trick" and not the best way to go (you should really be using the API to do it properly) but depending on how many courses you have, this may be a stopgap measure as you navigate the API. Hope this helps!