Hands-on activities are considered to be particularly suitable for generating long-term knowledge that increases environmentally friendly behaviour. Appropriate flagship species in a respective curricular context can enable high-quality education. We have developed a teaching concept and material for hands-on activities with bumblebees. This includes aspects of outdoor bumblebee-keeping in a teaching unit, together with the identification of bumblebee species and conservation activity in the context of biodiversity; bumblebees can act as umbrella species because their conservation needs incidentally protect other species. Moreover, the project involves keeping bumblebees indoors in a teaching unit that covers ethology and neurobiology. A total sample size of 188 German high school students from the fifth to seventh grade (lower and intermediate secondary-school levels) participated in the project. We measured students' knowledge about bumblebees in general and insect decline, as well as fear of bumblebees in a pre-test, post-test and follow-up test. Learning enjoyment was also measured in the post-test. Students acquired long-lasting knowledge and considerably enjoyed the learning experience. Fear of bumblebees decreased long-term, although knowledge that bumblebees can sting increased.