High protein shakes have become increasingly popular as nutritional supplements for adolescents, adults, and senior citizens. They are heavily advertised on television and in print media and are available in grocery and health food stores, at pharmacies, and from online distributors. In this project, students use colorimetric assays to determine the protein concentration of a particular product they bring to class and compare the results to the nutritional label. Students then use denaturing and nondenaturing polyacrylamide gel electrophoresis to characterize the protein composition of their protein shakes. These experiments promote critical thinking about common scientific procedures and should be of interest to both secondary school and college students.