Here are some issues that come up frequently. Tests test how well the student has learned. Therefore, unless the professor specifies otherwise, all examinations are to be completed by the student alone, without extraneous assistance of any kind. Whenever the professor permits an exception to any part of these rules, the exception applies only as far as specified by the professor. Such exceptions must be expressly permitted and cannot be presumed from prior exceptions on other tests.
Collaboration means working together.
Many classes emphasize working with a partner or in groups. Unless the professor specifies otherwise, it is assumed that all work submitted for a grade will be the product of the student's own understanding, and thus expressed in the student's own words, calculations, computer code, etc. When a student's work is identical or very similar to someone else's at points where individual variations in expression would be expected, it is reasonable for the professor to conclude that academic misconduct has occurred. Submitting the same assignment for a second class violates the assumption that every assignment advances a student's learning and growth. Unless the second instructor expressly allows it, submitting an assignment already submitted for another class is a form of academic misconduct.