This study explored how a free-space digital storytelling approach that advocates autonomy and creativity can be implemented in a formal elementary classroom and how it impacts students' language learning motivation and performances. Participants of the study were 64 sixth grade students in Taiwan. Following an experimental design, the data collected from three data sources, including motivation surveys, achievement test scores, and digital stories, were analyzed and triangulated. Two performance indicators of the digital storytelling, levels of language usage and levels of creativity, were found to have significant but different impacts on language learning. While the students' language usage performance in digital storytelling was significantly related to their achievement test scores, their creativity performance were significantly related to multiple motivation components, including extrinsic motivation, task value and elaboration. It was also found that the proposed digital storytelling approach had a positive impact on students' language performance and contributed to an increase to students' motivation in two dimensions: extrinsic goal orientation and elaboration, rather than intrinsic goal orientation. The results suggest that the positive impact of the proposed storytelling pedagogy resides in allowing students to stretch their creativity while demonstrating their language productivity, with the leverage of a holistic assessment scheme.