The purpose of the study was to determine the relationship between students' motivational orientations and their chemistry achievements and perception of learning within the original case of the hands-on approach to visible spectrometry. A total of 295 students from Polish and Slovenian vocational and technical high schools participated in the study. By applying the "k"-mean clustering procedure, two distinct clusters of students' motivational orientations were identified based on the SDT theory about autonomous and controlled motivation. Students classified as the good quality motivation group (Cluster II) outperformed students in the low quantity motivation group (Cluster I) in their knowledge gained through the hands-on approach and assessed the hands-on approach more positively with regard to their active participation in learning selected concepts from visible spectrometry. Altogether, the results of the present study confirm previous research findings about the importance of the quality of students' motivation for learning; the results show that hands-on laboratory work with autonomy-supportive teachers could create a motivating learning environment for students to learn with understanding and to cooperate with each other in academic tasks at a higher level of cognitive complexity. The main implication for teachers in chemistry classes is, therefore, to plan their teaching more systematically and creatively in order to provide students with individualised cognitively and motivationally challenging learning situations (both in terms of content and didactical methods) and to foster learning with understanding even within very abstract and cognitively complex learning tasks. (Contains 5 tables.)