This study employed an explanatory mixed methods design to examine the effects of two computer-based scaffolds on novice teachers' reflective journal writing. The context for the study was an attempt to refine the reflective writing component of a large scale electronic portfolio system. Quantitative results indicated that the computer-based scaffolds significantly enhanced the participants' reflective journal writing as well as the length of their written artifacts. Moreover, correlation analysis revealed that there was a positive relationship between the highest level of reflection and the length of journal writing. Three factors gleaned from qualitative data helped explain how and why the scaffolds enhanced participants' reflective thinking, including (a) the specific requirements conveyed in the scaffolds; (b) the structure of the scaffolds; and (c) the use of the critical incidents to anchor reflective journal writing. It is hoped that the analyses and results of the current study can help inform others on how to leverage the affordances of computer-based scaffolds to augment reflective practice in technology-enhanced educational systems.