In Study 1, 82 White children aged 5–10 years allocated rewards to White and Black target children in justified/unjustified normative contexts according to their performance on a previous task. In Study 2, 71 White children aged 5–10 years allocated resources to White and Black target children in conditions of high (interviewer was present) or low (interviewer was absent) salience of the anti-racism norm. In both studies, younger children displayed intergroup biased racial behaviours in most conditions, whereas older children, as expected, only displayed similar egalitarian behaviours in contexts where an anti-racism normative pressure was not salient. Results of both experimental studies highlighted the interplay between child development, the anti-prejudice norm and context factors. Furthermore, they support the assumptions of the theory of aversive racism regarding the use of legitimizing justifications to account for racial biased behaviours and extend its scope to a better understanding of the development of racial prejudice in childhood. Copyright © 2013 John Wiley & Sons, Ltd.