We hypothesized and observed that the degree to which students endorsed entity theories - the view that intelligence is fixed rather than malleable - attenuated the affective benefits and exacerbated the achievement drawbacks of positive fantasies in the academic domain. Positive fantasies only predicted low anger and anxiety for schoolchildren who did not strongly endorse entity theories (Study 1), and positive fantasies only predicted poor final school grades for vocational students who did strongly endorse entity theories (Study 2). An experiment indicated that for university students with stronger entity theories, positive fantasies demanded relatively little attention (Study 3), suggesting that positive fantasies obscure the opportunity for the preemptive self-regulation which promotes successful performance. (C) 2011 Elsevier Inc. All rights reserved.