This paper adopts scenario planning as a methodological approach and tool to help science educators reconceptualise their use of mobile technologies across various different futures. These "futures" are set out neither as predictions nor prognoses but rather as stimuli to encourage greater discussion and reflection around the use of mobile technologies in science education. Informed by the literature and our empirical data, we consider four alternative futures for science education in a mobile world, with a particular focus on networked collaboration and student agency. We conclude that "seamless learning", whereby students are empowered to use their mobile technologies to negotiate across physical and virtual boundaries (e.g. between school and out-of-school activities), may be the most significant factor in encouraging educators to rethink their existing pedagogical patterns, thereby realizing some of the promises of contextualised participatory science learning.