Secondary Students’ Accounts of Carbon-transforming Processes Before and After Instruction Purpose & Research Questions Pre-post Processes by Instruction Purpose: To examine the extent to which more targeted instruction is helpful in helping learners develop more atomic-molecular scientific understanding of carbon-transforming processes Research questions: How do students’ accounts of carbon-transforming processes in socio-ecological systems change as a result of instruction? How are changes in students’ accounts of carbon-transforming principles related to differences in instructions? Analysis & Findings Analysis: Based on pre-post assessments of 6 carbon-transforming processes Used exemplar workbooks developed based on sampled pre- post item responses & level of achievement Used matched-pair t-test Two key findings: Overall pre-post gains in students’ accounts in processes and principles among teachers (H & R) who used more targeted instruction No pre-post gains in students’ accounts in the process of growth among high school students Pre-post Principles by Instruction Commentary: Student Science Learning Learners face challenges regarding connected, in this case, carbon-transforming processes. This study responds to the call for reform-based science teaching (e.g. The National Research Council, 2007; National Science Standards, 1996) by extending work about helping learners to learn science in connected ways for meaningfully engaging in environmental decision making as informed citizens. Our preliminary findings suggest that: a) use of instructional materials for more targeted instruction holds promise for supporting learners move from force-dynamic reasoning to more model-based reasoning, and b) there is need for further work especially in the process of growth.