This paired text science unit focuses on helping students answer this Big Question: What causes Earth's Surface to Change? This unit contains two lessons and a unit assessment. Each lesson includes teacher support pages, a dictionary, a reading selection, and a variety of written and oral activities, including reading comprehension, close reading, vocabulary, and text-based writing activities. The reading selections in this unit are: Shifting Ground (Level T) and Washed Away (Level S). An answer key is also included.