Rocks are used in many different ways such as pebbles for paths, gravel for driveways, sand for castles, and clay for chimneys according to the document. Pebbles were used to create the path, gravel was used to build the driveway, sand was used for the castle, and clay was used for the chimney. The document provides examples of different types of rocks and how they are used for paths, driveways, castles, and chimneys.