Students are introduced to the "Walk the Line" challenge question. They are asked to write journal responses to the question and brainstorm what information they need to answer the question. Ideas are shared with the class (or in pairs and then to the class, if class size is large). Students then read an interview with an engineer to gain a professional perspective on linear data sets and best-fit lines. Students brainstorm for any additional ideas and add them to the list they produced already. With the teacher's guidance, students organize the ideas into logical categories of needed knowledge.