With a click of button I can find out what they think, if they are (collectively) lost, and generally keep them even more engaged that I usually do.
Students see this slide, we discuss it.

Then comes the clicker question:
What do you think comes NEXT?
A) allies re-invade Germany, collect taxes
B) US lends money to Germany to pay its debt
C) Allies lower reparations bills by 85%
D) Hitler rises to power, cancels debt
E) World Court rules T.of.Versailles illegal
Now having made their "guess" the students are more interested in learning about what really DID occur as a result of Germany's problematic economic situation.

And then we are ready to discuss whether lender-nations can truly ever be isolationist during times of escalating violence.
Have I mentioned how much I love my job?