This research studied a group of three preservice elementary teachers creating a narrated stop-motion animation (Slowmation) from start to finish in 3 hours to explain the challenging concept of “phases of the moon” to elementary school children. The research questions investigated the preservice teachers' learning before and after the construction as well as how the preservice teachers designed the slowmation as a teaching resource. Data collection involved individual interviews immediately before and after the construction in conjunction with analysis of video and audio data collected during the construction process. Before the animation construction, the participants had little understanding of the causes of moon phases and one held an alternative conception. After creating the slowmation all three preservice teachers demonstrated more “elements” of the concept and appeared to resolve an alternative conception. There are two findings from this research: (i) creating a slowmation enabled the preservice teachers to develop more elements to contribute to their understanding of moon phases; (ii) the design of the slowmation was based on breaking the concept into a sequence of sub-concepts that were represented digitally. Designing a digital teaching resource such as a slowmation to explain a concept involves preservice teachers breaking a concept down into coherent parts or “chunks” and representing the concept in multiple ways. This can be done within a science method class and is also a good way for the them to negotiate meanings about a difficult concept. © 2015 Wiley Periodicals, Inc. J Res Sci Teach 52: 1207–1233, 2015.