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-Along these lines--having buttons reading something like: "[Back] [Save and Continue] [Save] [Continue without saving]" could help mitigate issues from students not reading directions
this might cause confusion–too many options. another possibility:
"It may be useful to allow students just to continue without the submission but then when the time is up, whatever the temporary answer can be automatically submitted at the end without having them to explicitly submit."
-(why is this important? --) "Students may want to recheck their work and realize that they have made a mistake before the end of the exam. In this case, they should be able to change their answers. Of course, the new answer may be incorrect but it should be their choice."
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