A set of biochemistry experiments based on the technique of protein colorimetry is described. Students used the Biuret and Bradford assays to qualitatively and quantitatively assess solutions for protein. Two unique features of these experiments are (1) the use of intentional discrepancies within each experiment to promote critical thinking and (2) the use of authentic historical narratives to introduce critical concepts in the interpretation of assays and demonstrate the relevance of laboratory work to "real-world" scenarios. Details on the implementation and the evaluation of these experiments are discussed.