There are a number of pedagogical reasons for using interactive computer-based materials, such as those created with CALI Author. First, faculty members can use interactive materials to supplement the course's casebook. You can author a CALI lesson to expound on topics briefly covered, or missing, in the casebook. Second, faculty can elect to assign an interactive CALI lesson to teach fundamental concepts instead of covering the material in class. Then, during class time, faculty can focus on the more complicated issues, or application of the core principles. Third, faculty can use interactive materials to allow students to strengthen their understanding and to further work with the ideas initially covered in class. Sometimes, students just need another pass through the material to fully understand the concepts and their application. Often a CALI lesson can serve as that 'second pass." Students appreciate the chance to self-test their grasp of the material and to apply the new knowledge to various scenarios. An interactive CALI lesson, complete with self-assessment, provides concrete feedback to students that they often don't receive in law school until the final exam. Because lessons created with CALI Author are self-grading, students can quickly determine any deficiencies that they have with the materials. Students can also use the tutorials to strengthen their knowledge about a particular topic, or as a final review at the end of the semester. Many authors choose to write lessons with branching sections. Thus, the lesson is slightly different each time a student works through the material, as their route is determined by their choices.