The Institute of Medicine has warned of the harm of food marketing to children from television to new media channels such as the Internet. The authors identified and analyzed the techniques used to engage children on websites from cereal companies--the third largest food marketer to children. The authors found that top breakfast cereal manufacturers maintain child-oriented websites, using strategies unique to the Internet to capture and maintain children's attention. These include branded engagement techniques such as advergames, videos, site registration, and viral marketing, including inviting friends to join the site. The authors found 3 progressive levels of telepresence on child-targeted cereal websites: sites with more than 1 engaging feature, multiple techniques present on individual pages, and the construction of a virtual world. Using Internet traffic data, the authors confirm that these techniques work: cereal marketers reach children online with lengthier and more sophisticated engagements than are possible with traditional, passive media such as television advertisements or product packaging. Despite the cereal manufacturer's self-regulatory pledge to improve their marketing to children, their marketing practices exploit children's susceptibility to advertising by almost exclusively promoting high-sugar cereals using deeply engaging techniques.