Classroom teachers routinely make judgments on the quality of their students' work based on their recognition of how effectively the student has assembled key features of the genre or the medium. Yet how readily can teachers talk about the features of student-created multimodal texts in ways that can improve learning and performance? This article aims to address this issue by describing an approach developed by the authors for analysing and comparing the salient features of two multimodal texts created by the same secondary school student, one while in Year 8 (thirteen years) and one in Year 10 (fifteen years). Firstly, the criteria of design, content and cohesion are introduced as framing for the analysis. Next, these criteria are applied to the title slide, the slide headings and the knowledge representation in each multimodal text. The choice of the criteria and the product elements to which they are applied are central to our approach which aims to be practical and to provide sufficient coverage of key elements for descriptive and comparative purposes, especially the key multimodal features of the products. This approach has potential for wider application when two multimodal products are to be described and compared. (Contains 3 tables and 7 figures.)