This study compares two methods of instruction in practical school biology. The content remains the same but two teaching methods are used, one based on workstations (Group 1) and the other a conventional approach (Group 2). The content was a regular 9th grade syllabus issue: visual perception. Method 1 included a phenomenological introduction, collaborative and learner-centred phases as well as hands-on science activities. The study was conducted with 9th graders (n=125) of medium and highest ability streams at secondary schools. We assessed acquired knowledge in terms of anatomical and physical ideas and the understanding of visual perception. The comparison covered cognitive learning (measured on three different occasions: pre-test, post-test and retention-test) and emotional states. Both teaching methods led to a significant increase in conceptual knowledge, but produced different emotional effects. The pupils in Group 1 related the specific subject matter better to their personal future life than those in the conventional instruction group. However, participating pupils reported higher "well-being" scores in Group 1 and more boredom in the (conventional) Group 2: apparently pupils need to adjust to a new learning environment. Conclusions for practical work are discussed. (Contains 2 tables and 3 figures.)