Objective: to encourage children to drink more milk and reverse previous decline. Needed to transform image of milk drinking from 'good for you' (dull) to something more cool. Campaign associated drinking milk with sporting success with a focus on 'playground culture'. Target audience: slightly older children (10-15) in the hope that younger ones would copy them. Results: 12% increase in drinking over 5 years. A detailed study led to a hypothesis, supported by the evidence, about how playground crazes were stimulated by the advertising. This leads to a theory of wearout in advertising to children (since crazes are short lived and need constant renewal). Image of milk improved. The advertising paid for itself 3 times over.