We designed two NGSS-aligned middle school classroom experiments to investigate the effects of biochar on plant growth and soil respiration. Biochar is a carbon-rich material, produced by heating organic matter under limited oxygen, that is added to soils to improve fertility, to promote plant growth, and as one possible strategy to help mitigate climate change. The experiments offer an ideal case study for students learning fundamentals of soil and plant interactions. Soils and biochar are accessible, are connected to global issues such as agriculture and climate change, and are the focus of ongoing research in soil science. These classroom experiments promote authentic science because students design replicated experiments, collect and analyze data, discuss variability in the data, and interpret their results in the context of recent research.