Everything you need to understand or teach Lost Victories by Erich von Manstein.
Manstein was a career officer in the German Army and was Chief-of-Staff of Southern Army Group in the invasion of Poland in September 1939. Soon a Polish army was surrounded by the quick German Panzer tank troops and Warsaw was approached. The French declared war but refused to make a serious attack on Germany, and Poland was defeated. After the campaign, the question was how to defeat France and Great Britain quickly...
Lost Victories Lesson Plans contain 127 pages of teaching material, including: