This paper addresses the development in children's and adults' awareness of the benefits of writing through the analysis of change in notetaking while engaged in scientific inquiry over 10 weeks. Participants were given a notebook that they could choose to use. Our results indicate consistent differences between the performance of adults versus children and also across time. First, there were clear differences in the number of participants who chose to take notes. Second, not only did adults write more notes than children, but also the adults' mean number of notes slightly increased over time, whereas children's notes actually decreased in frequency. Third, children and adults differed in the types of notes they took. These results are interpreted in terms of participants' awareness of what needs to be noted in a scientific task and why it needs to be noted, and they suggest implications for educational practice. First, because learners often have inaccurate representations of the task demands and their own future state of knowledge, they do not perceive the utility of notetaking. Second, because of these misperceptions, learners do not refer back to their notes and thereby miss feedback that would spur the refinement of their metacognitive (particularly metastrategic) knowledge and strategy use. Educators need to design opportunities for students to engage in activities that increase metacognitive knowledge of their own cognitive abilities and the demands of the task. (Contains 1 table, 4 figures and 5 notes.)