In the case of children, the main products are unhealthy food, fashionware and entertainment goods. Children are a lucrative market: "...children 12 and under spend more than $11 billion of their own money and influence family spending decisions worth another $165 billion", but are not capable of resisting or understanding marketing tactics at younger ages ("children don't understand persuasive intent until they are eight or nine years old"). At older ages competitive feelings towards other children are stronger than financial sense. The practice of extending children's marketing from television to the school grounds is also controversial (see marketing in schools). The following is a select list of online articles: