The role of games within education becomes clearer as students become more active and are able to take decisions, solve problems and react to the results of those decisions. The educational board game "Discovering the Cell" ("Celula Adentro"), is based on problem-solving learning. This investigative game attempts to stimulate reasoning and interactivity in the classroom as it challenges students to collect, discuss and interpret clues in order to decipher a scientific question ("Case"). Here, we describe the conception, development and evaluation of "Discovering the Cell." The game was tested with students from public and private high schools in Rio de Janeiro, Brazil. A questionnaire-based analysis demonstrated how students had adopted this strategy. The majority, from both public and private schools, were able to solve a "Case," as well as apply the learned content when answering a "related question." Taken together, our results indicate the suitability of the game as an alternative strategy to help teach complex cell and molecular biology themes to secondary-level students. (Contains 4 figures and 2 tables.)