One way of making scientific concepts more accessible to students is to use active approaches, such as drama, in the classroom. The study reported in this paper evaluates the use of three dramatic improvisations performed by second year undergraduate students to improve their understanding of the generation and supply of electricity. Student improvisations were videotaped, and follow-up questionnaires and interviews were used in the study. The pedagogical advantages of using active learning in the classroom and the wider issues of drama's contribution to cognitive development are also discussed. (Contains 20 references.) (WRM)