Measuring hunger and satiety in children is essential to many studies of childhood eating behaviour. Few validated measures currently exist that allow children to make accurate and reliable ratings of hunger/satiety. Three studies aimed to validate the use of a new categorical rating scale in the context of estimated and real eating episodes. Forty-seven 6- to 8-year-olds participated in Study 1, which used a between-participant design. Results indicated that the majority of children were able to make estimated hunger/satiety ratings for a story character using the scale. No significant differences in the ratings of hunger/satiety of children measured before and after lunch were observed and likely causes are discussed. To account for inter-individual differences in hunger/satiety perceptions Study 2 employed a within-participant design. Fifty-four 5- to 7-year-olds participated and made estimated hunger/satiety ratings for a story character and real hunger/satiety ratings before and after lunch. The results indicated that the majority of children were able to use the scale to make estimated and real hunger and satiety ratings. Children were found to be significantly hungrier before compared to after lunch. As it was not possible to establish the types and quantities of food children ate for lunch a third study was carried out in a controlled laboratory environment. Thirty-six 6- to 9-year-olds participated in Study 3 and made hunger/satiety ratings before and after ingesting an ad libitum snack of known composition and quantity. Results indicated that children felt hungrier before than after the snack and that pre-snack hunger/satiety, and changes in hunger/satiety, were associated with snack intake. Overall, the studies indicate that the scale has potential for use with primary school children. Implications of the findings are discussed.