To prepare yourselves for the first spreadsheet session, glance over ...

MS Excel 2013 in Safari Books Online
  1. for some basic terminology you will be using
  2. Excel 2013 Courses and see if any are ones you need to view. You might want to bookmark all or parts of all of them.
  3. Part I: Worksheet Basics and Part II: Formulas and Functions in Excel 2013: The Missing Manual

These from can also be useful

As can these from Microsoft