A large body of experimental research on stereotype threat concentrated on immediate consequences of this effect. Far less attention has been given to the underlying mechanisms that may explain accumulative and long-term consequences of stereotype threat. To shed new light on the dynamic of stereotype threat, the current research examined the strength of associations between experience of stereotype threat, working memory, mathematical achievement and intellectual helplessness using structural equation modeling on representative sample in three age cohorts (13-16 years). Corroborating previous research, working memory was a significant and stable mediator of the relation between chronic stereotype threat and achievement across cohorts. Moving beyond past work, the results showed that mediation through intellectual helplessness was stronger in older cohorts, offering preliminary support to the hypothesis about an accumulative effect of chronic stereotype threat on mathematical achievement. Results are discussed in terms of motivational models of stereotype threat.