How can I set it up so that we can allow students to open a assessment more than once to continue answering questions or talk about their answers this is a fundamental requirement for our program?
You can set this up in your Assessment module settings area. There is an option to add lock settings (i.e. lock after x attempts) but you do not have to use it. In this case you would not want the module to lock at all. To set this up go in to your Assessment module from the Admin side, then click the 'Settings' tab and scroll down to the lock settings, uncheck the box or adjust attempt numbers as you like, then Save.
We built out a course all around creating Assessments in Litmos, check it out here: How To: Create an Assessment