This is a two-part/two-day lesson. Each lesson should take approximately 40-45 minutes. The majority of the first lesson is spent getting familiar with the idea of loans and terms associated with mortgages. This lesson begins with students discussing loans, and then specifically mortgage loans. Students calculate monthly payments for 30- and 15- year mortgages and then calculate the first year worth of individual payments. Students finish by examining a graph of the relationship between interest and principal payments monthly.