While some can see everything with an equation, others need to see it in multiple ways. Some of the least important comments you make will be some of the most remembered comments of the class. Finance is the most important and most encompassing class. Finance can be used to explain much of the world. The key is getting the students to understand the material, not memorize it.
Students can do much more than they think they can.
Raise the bar and students will go higher. Spreadsheets do not work well in showing concepts in classes of over 10. Use blackboards, Computer projecors, TVs, audio tapes, whatever can help you get your point across. Most students do not have the financial background to see why the material is relevant. One way the application of the material can be seen is with the use of examples.