I have an email filter that triggers on 2705 to put your incoming email into the class folder. The "mat" helps you remember that 2705 is a math course in your own email. [Try to put mat2705 in the subject header for any email you send me, for the same reason.]
I extract the attached file to a class folder to look at it, and without the partners' last names in the filename, I cannot find a given student's work to check that it was submitted there. By including this filename in the subject header, I can find if a student's work was submitted as part of a team by searching my email folder. Often students forget the CC so by having the partners names in the subject header I can autocomplete them back into the CC slots. [Make sure you use autocomplete for CC addresses, since typos often creep in here when hand typed.]
I need the CC so that I can "replyall" to the submission email message and attach the commented graded worksheet so you can learn from it or upgrade it by correcting errors or feel good about having submitted a perfect worksheet. Getting a reply is the only way you get confirmation that I graded an assignment for you. Not everyone submits every assignment but if I accidentally miss your submitted worksheet, you would eventually know since I did not return a grade.
The number of the maple assignment (equal to the chapter number of the corresponding problems) is important for finding a particular assignment by a particular student both in the mail folder (subject line) and in my PC worksheet folder (worksheet name).
Keeping all this bureaucracy straight is not so easy, and the more noncompliance, intentional or not, the harder my job is. The happier I am, the happier you should be with my assigned grades.