This data set (SENSO-Trail_Eval2021.csv) was created by an evaluation study for the SENSO-Trail concept, which is part of the LOEWE project Natur4.0 - Sensing Biodiversity. Six school classes (German Gymnasium) from Hesse participated 2021 in the study in pre-post-folow-up design. In a cleaned dataset, a total of 94 subjects could be analyzed by their provided data; 43 females and 50 males with an average age of 15.62 years (Min. = 14; max. = 18; SD = 0.86). A test group n = 66 (M = 15.85; SD = 0.83) and a control group n = 28 (M = 15.07; SD = 0.66) were created through a randomized assignment. In this context, it must be noted that in the follow-up examination with n = 50, a slightly lower response was achieved than was the case with the first two enquiries, which were conducted on the date of the actual intervention, directly before (pre, n = 66) and after (post, n = 66). The data was exclusively retrieved via anonymized paper- and pencil-style questionnaires at all three times of enquiry. The data set contains coded information about the participants biographic, affective and cognitive attributes.