Teacher presentation materials. Unit: Alg1.1 One-variable Statistics (Algebra 1). Alg1.1 One-variable Statistics In this unit on one-variable statistics, students discuss the difference between statistical and non-statistical questions and classify that data as numerical or categorical. They represent and interpret data using data displays, and describe distributions using the appropriate terminology. They create data displays and calculate summary statistics using technology, then interpret the values in context. They learn that standard deviation is a measure of variability, and they interpret standard deviation in context. They recognize outliers, investigate their sourc