The current Australian Curriculum mandates that technology be utilised to support students to "investigate, create and communicate mathematical ideas and concepts" (ACARA, 2018). However, research reports suggest that use of digital technologies in Australian primary mathematics often focuses on the lower-order drilling of algorithms and basic facts. In this study, an online environment provided the medium for Year 5 students to engage in collaborative mathematical problem solving. The students' online dialogue, along with uploaded diagrams and spreadsheets, provide evidence of their development of the Australian Curriculum: Mathematics' proficiencies of Problem Solving and Reasoning.