Electronic media, particularly television, have long been criticized for their potential impact on children. One area for concern is how early media exposure influences cognitive development and academic achievement. Heather Kirkorian, Ellen Wartella, and Daniel Anderson summarize the relevant research and provide suggestions for maximizing the positive effects of media and minimizing the negative effects. One focus of the authors is the seemingly unique effect of television on children under age two. Although research clearly demonstrates that well-designed, age-appropriate, educational television can be beneficial to children of preschool age, studies on infants and toddlers suggest that these young children may better understand and learn from real-life experiences than they do from video. Moreover, some research suggests that exposure to television during the first few years of life may be associated with poorer cognitive development. With respect to children over two, the authors emphasize the importance of content in mediating the effect of television on cognitive skills and academic achievement. Early exposure to age-appropriate programs designed around an educational curriculum is associated with cognitive and academic enhancement, whereas exposure to pure entertainment, and violent content in particular, is associated with poorer cognitive development and lower academic achievement. The authors point out that producers and parents can take steps to maximize the positive effects of media and minimize the negative effects. They note that research on children's television viewing can inform guidelines for producers of children's media to enhance learning. Parents can select well-designed, age-appropriate programs and view the programs with their children to maximize the positive effects of educational media. The authors' aim is to inform policymakers, educators, parents, and others who work with young children about the impact of media, particularly television, on preschool children, and what society can do to maximize the benefits and minimize the costs. (Contains 1 table and 81 endnotes.)