1) "1. Students may write long posts and then suddenly encounter an error message that causes them to lose what they’ve typed.
Response: This should not happen, but if so, I can tell students to write in Word and then post as an attachment, or to save in Word as a backup, or even to copy and paste the text before clicking Publish."
Never, ever c & p from Word or Office or any rich text editor directly into WP. The extraneous characters added by Ms products will completely screw up your blog. If one of these must be used, c & p from Word into Notepad (or any basic editor) and save it - then c & p into Wp. This strips the unwanted crap. Also, you shouldn't c & p from your browser without going through Notepad.
5) "25 students working in the WordPress admin console at one time may cause unwanted slowdowns.
Response: According to WordPress techies, WordPress should be able to handle 25 students in the admin console at one time no problem."
25 students won't be a problem for WP. I had 41 at one time on a test blog just to see what it would handle.
7) "Students may become more familiar with writing in the WordPress text box rather than Microsoft Word."
One can only hope. :>)
11) "11. Students may encounter formatting errors with the text editor that they can’t solve.
Response: The text editor only offer simple formatting, but if students run into problems, they can always paste their content in Notepad to strip unwanted tags."
I think you will do well as you've anticipated possible problems and have a plan. You can always come back here for help and don't worry - WP is quite a robust creation.