Biochar is being actively explored as a tool for long‐term soil carbon sequestration. However, in order for this to be effective the long‐term environmental stability of biochar must be assured. Here, we define and test an accelerated ageing method that seeks to reflect the oxidative nature of biochar degradation in soil. The method was applied to a systematic set of biochar samples produced from sugarcane bagasse, and a set of biochar samples produced from four different biomass sources. The stability of carbon in these samples was found to range between 41.6% and 76.1%, loosely correlating with biochar O : C ratio (r = 0.73). Increasing intensity of oxidative treatment eliminated more carbon. It also increased surface O : C ratio in a manner reported for naturally aged charcoal samples. The method effectively discriminated biochar produced under contrasting pyrolysis conditions and could be used as a proxy for environmental ageing of approximately 100 years under temperate conditions.

How can we best leverage higher education to address the pressing issues we face? While the SDGs reflect a global landscape dominated by complex, interconnected ‘wicked’ problems, Higher Education Institutions (HEIs) remain largely tethered to siloed, decontextualized instructional models. The inability of HEIs to shift practices to foster transversal, 21st-century skills necessary to navigate uncertain futures is a critical competency gap. This paper highlights the transformative potential of challenge-based learning (CBL) and place-based learning (PBL), high-impact experiential pedagogies, as critical tools for sustainability transformations. The Consortium for Adaptive Futures, an interdisciplinary and transnational community of practice, was launched in early 2025 to promote co-learning among faculty from North America and Europe for these practices. Drawing on insights from an inaugural symposium in Dublin, we identify three critical elements to HEI transformations that support sustainability and 21st-century skills to address grand challenges. These are: the importance of real-world relevance in education; the need for pedagogical shifts and faculty development to support these new roles; and the essential role of supportive institutional structures and resources to enable sustained engagement. In doing so, we issue a call to arms to HEIs and forward a reimagining of undergraduate education.