brainstorm for customizations

hi all, we are looking for some customizations of the system. 1 we need course video to be randomly interrupted by quizzes. is it possible to implement? or do you have any idea on how to set this up with little coding? 2 we need to allow instrutor open the (pdf?) assignment, write over it corrections, and save. <span style="line-height: 1.5;">is it possible to implement? or do you have any idea on how to set this up with little coding?</span> if you have any idea we can also set up useful existing plugins, test integration with wplms, and share results