Despite the increasing use of portable tablets in learning, their impact has received little attention in research. In five different projects, this media-ethnographic and design-based analysis of the use of portable tablets as a learning resource in science museums investigates how young people's learning with portable tablets matches the intentions of the museums. By applying media and information literacy (MIL) components as analytical dimensions, a pattern of discrepancies between young people's expectations, their actual learning and the museums' approaches to framing such learning is identified. It is argued that, paradoxically, museums' decisions to innovate by introducing new technologies, such as portable tablets, and new pedagogies to support them conflict with many young people's traditional ideas of museums and learning. The assessment of the implications of museums' integration of portable tablets indicates that in making pedagogical transformations to accommodate new technologies, museums risk opposing didactic intention if pedagogies do not sufficiently attend to young learners' systemic expectations to learning and to their expectations to the digital experience influenced by their leisure use.