Cultural probes for environmental education: Designing learning materials to engage children and teenagers with local biodiversity

between 15 and 18. Most participants (n = 33) joined the reflective post-trail activity per- formed at the university a month and a half later. Regarding participants’ exposure to local biodiversity, we note that teachers working with the Azorean primary and middle school curricula can adapt content and materials to the region’s socioeconomic and environmental context [35]. This flexibility offers teachers space to include subjects concerning local Azorean biodiversity, the region’s protected areas and its context-specific environmental issues. However, because the curricula are flexible, it is difficult to know with certainty and depth which Azorean living organisms, protected areas, and envi- ronmental issues students explore in class. However, following our communication with the Directorate of the Natural Park of Terceira, only 10.4% of the islands’ students visited the park during the period previous to the COVID-19 pandemic, 2018–2019 [36]. Data collection methods. In this study, we first developed a CP toolkit with the Azorean natural forest ecosystems in mind. We then implemented the toolkit during a trail walk with local children and teenagers. We collected data based on questions formulated by the partici- pants and their final impressions from the trail walk. Later, we conducted a post-trail activity in a classroom setting, where we asked participants about their willingness to return to the trail and why. For its construction, we adopted the six categories commonly used applying the CP tech-

nique, as documented by Thoring et al. [22]: (1) "document”, (2) "envision", (3) "inspire", (4) "motivate", (5) "instruct", and (6) "support". We describe the toolkit, in greater detail in the fol- lowing sub-section. Approximately two months after the trail walk, we invited participants to a follow-up activity at the University of the Azores. By adopting a descriptive research design, and mixed-methods approach that made use of surveys and observations for collecting both quantitative and qualitative data, we were able to assess the CP’s: 1. Efficacy in promoting productive questioning for the future development of EEM (RQ1). 2. Effectiveness in promoting sensory, emotional, and aesthetic experiences in nature (RQ2). 3. Potential to positively engage youth with nature-rich environments (RQ3). As detailed in Table 1, we assessed productive questioning by looking at the ratio between the questions motivated by a need to obtain an answer (and therefore obtain or confirm knowledge), and questions formulated to satisfy a request (i.e., in response to the toolkit’s sug- gestion that participants pose a question following each activity). While the first group corre- sponds to productive questions, the second group corresponds to strategic questions. Here, it is important to note that we do not treat the questions individually as such although they are essential to the FG project in signaling themes we may wish to act upon in the subsequent development of the project. Table 1. Analytical model of the CP technique’s efficacy. Constructs Dimension Indicators

Productive questioning Type of questions Type of approach to the task of questioning Experiences in nature Sensory, emotional, and aesthetic experiences Dominant theme of the final responses Engagement with nature-rich environments Satisfaction Degree of the evaluative judgments of the final responses Willingness to return to the trail Motivation Semantic field of the motives of satisfaction of the final responses Focus of the motives to return to the trail https://doi.org/10.1371/journal.pone.0262853.t001 PLOS ONE Cultural probes for environmental education PLOS ONE | https://doi.org/10.1371/journal.pone.0262853 February 10, 2022 7 / 30