One of the most useful functions IMO is SUMPRODUCT. That combined with SUMIF and COUNTIF are often invaluable for anyone with tables of data that needs interrogating.
One very useful tip is how to convert what should be numerical data that has been copied in from somewhere else, but has come in as text, and as such will give a 0 when summed etc. That tip is the 'copy an empty cell, select the data conncerned and do edit / paste Special / add' which coerces it back to numeric.
Another thing you might consider is to advise them of resources such as this forum, where anyone with Web access can go and get help.
I completely agree with the comments re Pivot tables - as these are one of the most powerful, yet simple to use features Excel actually has.
There are also a number of good websites that you may want to let them have, which once their appetite has been whetted will allow them to go and expand on what they have seen:-
Chip Pearson's Site, one of the best all round references on the web:-
John Walkenbach's site - Probably the most prolific Excel author today, with a whole string of superb Excel books to his name:-
Debra Dalgleish's site - A great reference for a number of things, but especially for introducing filters and pivot tables:-
Dave McRitchie's site - A prominent Microsoft MVP with a whole host of goodies on his site - my favourite being his 'Trimall' macro, which will clean up any data brought in from the web into Excel:-
Ron De Bruins's site, another Microsoft MVP, with some great addins, especially his Google search addin that allows you to search newsgroups directly from Excel, and his sendmail addin.
The Excel MVP page - a collection of free utilities from a number of Microsoft MVPs:-
Tushar Mehta's site (another MVP) - a huge compendium of all things Excel - Some great Technical and mathematical stuff in there:-
A superb freely downloadable set of examples from Peter Noneley:-
Another excellent Tek-Tips type forum
An oft asked question is how do I convert a file from Works to Excel - Worry no more:-
The Excel Newsgroups themselves, from within a Google interface:-
Standard Interface
Advanced Interface
(All this is available through Ron De Bruins addin, and is probably easier to use)
The Microsoft KnowledgeBase
Direct access via the web to Microsoft's newsgroups:-
A free Excel viewer that allows people without Excel to view Excel files (useful if sending docs to other people):-
Either a page on an intranet with examples of some of the suggestions you have had, or perhaps a sample workbook with a lot of the examples listed, plus some good weblinks might be a nice giveaway for the class.
Hope this helps:-
Regards
Ken.....................
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