This document discusses classifying and identifying different types of angles. It defines an angle as two rays that share an endpoint, called the vertex. There are four main types of angles: acute angles which are less than 90 degrees; right angles which are exactly 90 degrees; obtuse angles which are greater than 90 but less than 180 degrees; and straight angles which are exactly 180 degrees. The document provides examples of identifying different angles in illustrations and classifying them by type, as well as group activities for students to practice classifying and creating examples of different angle types.