Simulation programs allow students to make decisions and models that simulate real-life problems and situations. They teach strategies and rules while allowing students to manipulate elements and see the effects of their choices. Examples include SimCity and Thinking Things 1. Instructional games add elements of competition and challenge to engage students, such as GeoSafari. Multimedia encyclopedias like Eyewitness Children's Encyclopedia can store huge databases with various media like texts, images, and videos. Electronic books provide textual information supplemented by multimedia for reading and skills practice, exemplified by Just Grandma and Me.