This study investigated the effectiveness of three different instructional materials for learning how to identify fish at the species level in a blended classroom and out-of-classroom scenario. A sample of 195 first-year students of biology or geoecology at the University of Tuebingen participated in a course on identification of European freshwater fish species at a public aquarium. Prior to studying the species in the aquarium's fish tanks, students prepared themselves in a classroom nearby with one of three different learning materials: (1) preserved specimens and paper-based dichotomous identification keys; (2) digital videos; or (3) digital videos with preserved specimens and paper-based dichotomous identification keys. Students' acquisition of knowledge and their motivation were measured twice, once after preparing in the classroom and once after visiting the aquarium. Results showed that students who had prepared themselves with digital videos identified significantly more species correctly but were less motivated than those students who had learnt only with preserved specimens and dichotomous identification keys. When both instructional methods were combined students performed well in the post-tests and were motivated to learn, suggesting that the combination of both instructional approaches encourages motivation without any outcome losses.