In this study we designed a module of twenty lesson plans on the history of mathematics for implementation in transition year in a second level school. The module was implemented by the first author in a transition year class in an all girls school. Student provided feedback before, during and after the module and we analysed their feedback. The two main results of our qualitative analysis are that there was an instant change of all students’ perception of mathematics for the better after the first lesson plan and also that there was s sustained change of all students’ perception of mathematics for the better after all twenty lesson plans. This shows that the history of mathematics has a powerful immediate (and sustained) positive impact on students’ perception of mathematics. We also discuss some positive changes in students; attitudes in relation to mathematics and humanity, creativity, beauty, practical power and history. We feel this paper helps to fill a gap in the current research on using the history of mathematics in second level schools in Ireland.