We will develop and research a teacher training course that introduces an innovative learning practice using eye-tracking vignettes. Our aim is to support mathematics teachers in (further) developing their statistical PCK and CK. These knowledge facets are required if teachers are expected to prepare their students to become data literate citizens of civil society. Our training course will provide teachers with learning opportunities to (1) diagnose and (2) deal with students' statistical (mis)interpretations as well as to (3) overcome their own statistical difficulties.