The use of (educational) escape games in science education is becoming increasingly popular. It is an innovative, motivating way to teach this subject area in a new way that is relevant to learners’ everyday lives, especially for topics related to sustainable development, including biodiversity and its conservation. This study aims to design and evaluate an educational escape game (EEG) on biodiversity conservation. The research questions address game experience as well as advantages and disadvantages of integrating an EEG into the classroom. For this purpose, 25 high school students and 32 pre-service teachers played the EEG. They evaluated the game experience in a post-survey. All participants found the EEG motivating and suitable for biodiversity learning. Teamwork was also appreciated. However, knowledge acquisition was perceived as limited compared to traditional teaching: one reason given by the students was the lack of challenge. Pre-service teachers attributed this to time pressure and distractions caused by the game. Despite limitations such as the lack of a control group and the small sample size, the study’s description of the advantages and disadvantages of using EEGs in the classroom offers a promising approach for designing motivating, learner-centred lessons on biodiversity and provides opportunities for further research.