Let it snow! If you want to teach your students all about snow crystals, this is the perfect slide show. It corresponds page-by-page with the book The Story of Snow: The Science of Winter's Wonder. However, it can also be used without the book as a stand alone lesson. It teaches how snow crystals form, what shapes they can be, how to catch a snowflake and more. There are 13 slides filled with important facts about snowflakes.