The purpose of the present study was to investigate whether changing children's beliefs about the controllability of obesity would reduce their negative attitudes toward fat people. The participants were 74 children from Grades 4-6, 42 in the experimental group and 32 in the control group. The experimental group were presented with a brief intervention which focussed on the uncontrollability of weight. The study found that the intervention was successful in reducing the amount of controllability that children assigned to obesity, but was not successful in reducing negative stereotyping of the obese among the experimental group compared to the control group. These results indicate that while children's beliefs about the controllability of obesity can be changed, reducing their negative stereotyping is more difficult.