Plagiarism and Punctuation and Grammar: at every school these are basic issues that absolutely must be addressed for your new students. But there is only so much in-class time to devote to these issues.
We highly recommend school administrators, faculty, and students take a look at CALI's Plagiarism Lesson by Prof. Rebecca Trammell and Punctuation and Grammar, Basic and Advanced, Lessons by Prof. Wayne Sheiss.
We know many schools that have students sign a statement confirming they read a plagiarism/ethics code. But the plagiarism lesson actually makes students think about and recognize the issues involved. So assign this lesson to your incoming students as well.
And students, if not assigned by your school, give the Punctuation and Grammar lessons (part 2/advanced here) a try on your own to brush up on grammar for your legal writing classes before you get too busy.