Mathematica is a computer program used widely in scientific, engineering and mathematical fields that seamlessly integrates a numeric and symbolic computational engine, graphics system, programming language, documentation system, and advanced connectivity to other applications. It is this range of capabilities that makes Mathematica uniquely capable as a "one-stop shop" for your technical work with students.
Free Online Seminars
http://www.wolfram.com/services/education/seminars/
Free Online Screencasts
http://www.wolfram.com/broadcast/screencasts/
Full Documentation
http://reference.wolfram.com/mathematica/guide/Mathematica.html
Guidepages Showing Full List of Available Commands
Statistics Guide - http://reference.wolfram.com/mathematica/guide/Statistics.html
Bar Charts Guide - http://reference.wolfram.com/mathematica/BarCharts/guide/BarChartsPackage.html
Histograms Guide - http://reference.wolfram.com/mathematica/Histograms/guide/HistogramsPackage.html
Curve Fitting Guide - http://reference.wolfram.com/mathematica/tutorial/CurveFitting.html
Example Demonstrations
Business - http://demonstrations.wolfram.com/topic.html?topic=Business
Economics - http://demonstrations.wolfram.com/topic.html?topic=Economics