Guided-inquiry lab activities with bean beetles ( Callosobruchus maculatus ) teach students how to develop hypotheses, design experiments, identify experimental variables, collect and interpret data, and formulate conclusions. These activities provide students with real hands-on experiences and skills that reinforce their understanding of the scientific method and experimental design. This teaching method can easily be adapted to other test organisms or alternative themes.

Implementation of a guided-inquiry lab in introductory biology classes, along with scaffolded instruction, improved students’ understanding of the scientific method, their ability to design an experiment, and their identification of experimental variables. Pre- and postassessments from experimental versus control sections over three semesters showed that most students improved in their understanding of the scientific method and experimental design skills. Students exhibited improvement in their ability to create hypotheses and correctly identify controls and dependent variables. However, students in both groups struggled with the identification of independent variable and controlled variables.