Look into the Cover Page Building Blocks in Word. Once you have a good model, you can save it as a Cover Page in a template and let your students use it. Look at the ones that are built-in and study their components and methods. A key component is the
document property content controls.
You should set it for 12 pt TNR with either no space between paragraphs or multiples of 12.
I know a lot of people prefer sans serif fonts, but with proportional fonts, there is research that body text is more readable in serif fonts. I generally use a serif font for body and a sans serif for headings.
If your students are going to be working in Word, introduce them to Shauna Kelly's site. It will save them a lot of frustration.
Basic Concepts of Microsoft Word - from Shauna Kelly
Introduce them to styles, especially the built-in heading styles.