This paper addresses a gap in the literature on primary student-teachers' use of graphics calculators. A group of 12 student-teachers, specialising in mathematics, engaged in a mathematical task as learners, and then adapted the task for primary pupils. Their lesson plan included graphics calculators, which the student-teachers taught to a class of primary pupils as part of their placement. Recordings of discussions, and notes from the lesson observations, were examined using the TPACK framework (Koehler et al, 2013). Findings suggest student-teachers are strongly influenced by their prior experiences and beliefs about graphics calculators. Despite demonstrating good levels of TPACK, student-teachers' beliefs and attitudes re-emerged and superseded their positive experience of teaching with graphics calculators. The 'TPACK +' framework is proposed, which recommends that beliefs and attitudes should be taken into account, as well as technological, pedagogical and content knowledge.