Description Beginning readers learn all about sand dunes while decoding words with silent e. Sand dunes are hills and slopes of sand. They form when the wind blows and shifts sand around. Beginning readers hone their phonics skills while learning all about these landforms. As readers practice decoding words with silent e, they gain science knowledge. Every Stairway Decodables nonfiction book combines multiple aspects of the Science of Reading to support small group instruction, independent reading, and reading practice at home.