The power and value of mathematics cannot be underestimated. Mathematics is essential in the workplace, for economic growth, for technological advancements and as part of our cultural heritage. Despite this, research reports that second-level students do not appreciate the value of mathematics and fail to see its relevance. One potential reason for this is that they are not exposed to the usefulness of mathematics because their teachers are unaware of the applicability of the subject. This study, conducted with 17 pre-service mathematics teachers [PSTs], sought to determine PSTs' levels of understanding of the value of mathematics, and in particular rational numbers. With baseline levels of understanding established it then sought to determine the impact that a short intervention had on PSTs' understanding of the important role that mathematics plays in the world around us. The results show that despite PSTs having low levels of understanding of the utility-value of mathematics to begin, a short intervention resulted in significant improvements in this dimension of understanding. Thus, the authors argue that interventions such as that described should be seen as integral components of undergraduate teacher training programmes due to the impact they can have on a teacher's ability to teach for understanding.