Future elementary school teachers often lack self-efficacy for teaching science and technology. They are particularly anxious about encouraging children to carry-out student-directed, open-ended scientific inquiry and/or technological design projects. Moreover, because this often also is the case with practising elementary school teachers, it is difficult for student-teachers to gain practical experience facilitating student-led project work during practicum sessions. To provide student-teachers with expertise and motivation for promoting student-directed, open-ended project work, therefore, a group of future elementary teachers were taken through a constructivism-informed "apprenticeship" during their university-based teaching methods course and then invited to make project work the subject of the action research that they were required to complete during their practicum. In this paper, successes that one student-teacher (out of 78 studied) experienced in promoting student-directed, open-ended technological design projects are reported. Although she judged children's designs to be modestly successful, data indicate that her self-efficacy for promoting project work increased significantly. Analyses of qualitative data collected during the methods course and practicum also indicate that aspects of the "curriculum," "teachers," "students" and "milieu" appeared to contribute to this success. Such findings suggest that teacher educators should focus on helping future elementary teachers to develop expertise and motivation that would enable and encourage children to conduct technological design projects before conducting scientific inquiries. Such a tack may be the most pragmatic--and, arguably, epistemologically-sound--approach for helping "science- and technology-phobic" student-teachers to move from the periphery to the core of practices in science and technology education.