In this study, defensive pessimism is reviewed in relation to anxiety, self-esteem, expectations, self-regulation, and self-handicapping. Then, two case studies of American pre-service teachers in a mathematics classroom are provided that move the research beyond survey and correlational studies. In the case analyses, defensive pessimists' discourse and behaviours are examined and additional characteristics are noted, e.g., expressions of humour and self-congratulations. In connection with teaching, teachers are encouraged to support defensive pessimists' learning strategies, such as perseverance and the use of multiple representations, so that the focus is on meaningful learning instead of the negative self-talk.