Interest within the chemistry education community in incorporating sustainability into chemistry education has converged on a systems thinking approach, and efforts to implement this are ongoing. One challenge to implementation is the different amenability to systems thinking approaches of topics that are important in chemistry at the secondary-tertiary interface. To identify low-hanging fruit, we developed a repertory grid consisting of five poles mapped to elements of systems thinking. Secondary and tertiary educators completed the grid during workshops, to measure the amenability of 12 chemistry topics that are important in both secondary and tertiary chemistry education to teaching through systems thinking approaches. Three of the 12 topics analyzed were considered highly amenable to systems thinking approaches by both secondary and tertiary participants. The level of teaching experience was found to be most significant in determining a participant's perception of amenability of topics. The relationship of these topics to the curriculum structure at the secondary and tertiary level is discussed.