Educational digital storytelling is widely recognised as a powerful approach in developing literary skills, experiencing problem-solving and computational thinking, information and knowledge visualisation, building creativity and divergent thinking supported by technological solutions. However, educators feel that they miss opportunities, skills, and tools to support pupils developing creativity. Hence, we proposed a digital learning environment, named Novelette, to support both educators and learners in performing visual storytelling by scaffolding them in inventing and authoring stories. The main novelty of our approach lies in embedding literary artifices widely explored in learning settings into a digital learning environment, such as the opportunity to continue someone else’s story and the suggestion mechanism to explore analogies or synonyms starting from a word of interest. Novelette has been ideated not only as a learning environment for educators, but with educators, as it results from a user-centered and participatory design methodology to involve them in the entire design and development process actively. This paper focuses on the assessment of Novelette usability according to both educators and pupils. As a conclusive step of the co-design approach, developers tested the resulting usability according to educators in a controlled environment. Moreover, it reports usability according to learners in real settings at school. Results demonstrate that Novelette is considered usable by both target groups, and it is perceived as a powerful approach in developing creativity both according to quantitative insight offered by the System Usability Scale, a.k.a., SUS, and qualitative interpretations enabled with direct observations and structured after scenario questionnaires. We can conclude that Novelette is a pleasant and usable tool to invent and author stories and seems to be a promising approach to develop creativity.