Any "must do's" for 3 days in Quebec with 2 teenagers? I'm having trouble distilling the lists in Fodors Guide. Thanks.

Montmorency Falls can be quite impressive, especially after heavy rain. They are about 15 minutes from the city center by car or bus. There is also a ship called the Louis-Joliet (I think) that cruises up and down the St-Lawrence, offering spectacular views of the city. Or you could just let your kids roam the historical parts and soak up the atmoshere.