The lesson plans and mathematics resources contained on this website were originally designed as five-week curriculum units for a joint summer school program between the Stanford Teacher Education Program (STEP) of Stanford University and the Santa Clara Unified School District in Santa Clara, California. The summer classes included a mix of students entering 7th or 8th grade who had either signed up voluntarily for the program or were required to attend summer school by their guidance counselor or principal. Unit I, "Understanding Rational Numbers", includes lessons that were written for 110-minute class periods, but which can be easily broken down into shorter periods. Most of the lessons in Unit 2, "Problem Solving Like a Pro", were written for 70 minute classes. A few lessons were written for shorter periods due to school assembles or other school wide activities. In addition to developing an understanding of the mathematical content of each unit, the lessons were designed to build students' confidence in doing math and to encourage students to find multiple ways to communicate their understandings about mathematics. Please read the table of contents (Forward to Teachers, History and Acknowledgments, How to Use This Site, and Problem Sources and Citations) in order to make the best use of this website.