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

RESEARCH ARTICLE Cultural probes for environmental education: Designing learning materials to engage children and teenagers with local biodiversity So´ nia MatosID1,2☯*, Alexandra R. Silva1,3☯, Duarte SousaID1, Ana Picanc¸ oID3, Isabel R. AmorimID3, Simone AshbyID1,4, Rosalina GabrielID3, Ana Moura Arroz3☯ 1 Interactive Technologies Institute (ITI/LARSyS), Polo Cientı´fico e Tecnolo´gico da Madeira, Caminho da Penteada, Funchal, Portugal, 2 School of Design, Edinburgh College of Art, The University of Edinburgh, Edinburgh, United Kingdom, 3 cE3c –Centre for Ecology, Evolution and Environmental Changes / Azorean Biodiversity Group, University of the Azores, Azores, Portugal, 4 Tilburg School of Humanities and Digital Sciences, Language, Communication and Cognition, Tilburg University, Tilburg, The Netherlands ☯ These authors contributed equally to this work. * sonia.matos@iti.larsys.pt Abstract Direct contact with nature is paramount in deepening children’s and teenagers’ interest in biodiversity. Learning materials chosen to convey information and engage participants dur- ing outings in nature-rich environments are varied and can support rich learning experi- ences. For this purpose, learning materials can be acquired "off-the-shelf" or developed for site-specific locations or projects. However, there is little guidance on potential techniques for those wishing to generate contextually relevant materials. With the view of responding to this challenge, we propose the cultural probes technique. We demonstrate that the tech-

nique, commonly used in qualitative research to generate novel insights in conversation with participants, can instigate innovative and thoughtful approaches to materials designed for children and teenagers to explore nature. We present a toolkit that draws on the literature on cultural probes, inquiry-based learning, and the value of sensory, emotional, and aes- thetic experiences in environmental education for structuring interactions with participants. To test our approach, we applied a descriptive research design and mixed-methods approach for collecting questions from youths between the ages of 10 and 18, inspired by a nature walk and a set of exploratory tasks executed through the toolkit. Specifically, we tested our toolkit along a trail in the Nature Park of Terceira, situated in the Azores, a Portu- guese volcanic archipelago in the North Atlantic. Here, we present and reflect on the data collected during one visit organized over two days with two groups of participants and one post-trail activity directed at both groups. Results demonstrate that the open-ended and playful nature of cultural probes offers a novel way to engage youths with nature-rich envi- ronments through questioning. This contribution further highlights the potential of cultural probes for instigating encounters that tap into the value of sensory, emotional, and aesthetic experience in nature, with positive outcomes for participants. PLOS ONE PLOS ONE | https://doi.org/10.1371/journal.pone.0262853 February 10, 2022 1 / 30 a1111111111 a1111111111 a1111111111 a1111111111 a1111111111 OPEN ACCESS

Citation: Matos S, Silva AR, Sousa D, Picanc¸o A, R. Amorim I, Ashby S, et al. (2022) Cultural probes for environmental education: Designing learning materials to engage children and teenagers with local biodiversity. PLoS ONE 17(2): e0262853. https://doi.org/10.1371/journal.pone.0262853 Editor: Paulo Takeo Sano, University of Sao Paulo, BRAZIL Received: February 17, 2021 Accepted: January 6, 2022 Published: February 10, 2022 Copyright: © 2022 Matos et al. This is an open access article distributed under the terms of the Creative Commons Attribution License, which permits unrestricted use, distribution, and reproduction in any medium, provided the original author and source are credited. Data Availability Statement: All relevant data are within the paper and its Supporting Information files. Funding: Field Guide is supported by FCT - Fundac¸ão para a Ciência e a Tecnologia a Portuguese public agency that supports science, technology and innovation, in all scientific domains. FCT project reference number: PTDC/ CED/EDG/31182/2017. Isabel R. Amorim participation was funded by Portuguese funds through FCT – Fundac¸ão para a Ciência e a

Introduction Environmental Education (EE) strives to create "opportunities to explore nature in the out- doors", to provide "information about conservation and environmental issues", and to convey "knowledge and skills that can be used to defend, protect, conserve, or restore the environ- ment" [1]. To this end, EE also often "encourage(s) different ways of generating meanings of, valuing, conceiving, and contextualizing "nature"" [2]. Paired with EE’s interest in "collective and community learning and action" [3], in this study, we propose the cultural probe (CP) technique as a novel and meaningful approach in EE to engage children and teenagers with local biodiversity. Drawing on Ardoin et al.’s "exploration of future trends in environmental education research" [3], EE, as a field, includes work from both "natural and social science" and therefore is a "multidisciplinary, interdisciplinary, and transdisciplinary field". Nonetheless, "the two fields that most pre-dominantly engage in EE" are "Education and Communication" [1]. While research produced by EE will often focus on "the integration of EE into formal schooling", the field also contributes knowledge that reflects on "informal settings" [3]. Its contributions also have implications for both the theory and practice of EE. Perhaps, most notably for our proj- ect, the field has come to stimulate" (. . .) researchers to think pedagogically from the student/ learner perspective" [3]. As in any field of scientific inquiry, EE "is also continually evolving",

whereby "more recent approaches seek to focus on the social dimension of environmental challenges, to more actively address behavior change, and to facilitate rather than lead learn- ing" [1]. Environmental education materials (EEM) can be key in supporting meaningful interaction with nature, both the classroom and in outdoor settings. When developing and designing printed leaflets, books, audiovisual materials, websites, and content for digital devices, it is essential to consider that “materials should acknowledge that feelings, experiences, and atti- tudes shape environmental perceptions and issues” [4]. For example, EE guidelines, written in support of EEM, highlight the importance of "fairness, accuracy, depth, skills and action build- ing support, instructional soundness, and usability" of materials [4]. Yet, while the literature devises criteria to help those involved in EE select suitable existing EEM [5], there is less sup- port for those wishing to generate context-specific materials. EE guidance indeed recognizes that materials should “meet the specific needs of the site or community where they will be employed", stating that "content should emerge from and address the needs of a local community" [6]. In fact, “pre-formulated” and “off-the-shelf mate- rials” might not always be efficient and can be replaced by the collaborative creation of tools for education for sustainable development [7]. When working with specific communities, con- text specificity should reflect the “place” of a community as well as its “identity” or “shared interests” [8].

We developed this study in the Azores, the northernmost of the four Macaronesia archipel- agos featuring a Mediterranean hotspot of biodiversity [9], characterized by high levels of endemism [10, 11] and important areas of native vegetation [12], including relict species. Not- withstanding, exotic invasive species (e.g., Hedychium gardnerianum, Pittosporum undula- tum), climate change [13, 14], the building of new infrastructures within protected areas (e.g., roads, geothermal facilities), the degradation and fragmentation of habitats due to human activities such as intensive pastures and urbanization [15], pose significant threats to the con- servation of these unique habitats [16]. As a backdrop to the study, we have Field Guide (FG), a project [17] comprising a team of researchers, many of whom are based in the Azores, with expertise in the fields of biology, nature conservation, environmental education, environmental psychology, and human- PLOS ONE Cultural probes for environmental education PLOS ONE | https://doi.org/10.1371/journal.pone.0262853 February 10, 2022 2 / 30 Tecnologia, I.P., under the Norma Transito´ria – DL57/2016/CP1375/CT0003. Competing interests: The authors have declare that no competing interests exist.

computer interaction design. The project’s overarching objective is to develop, design, and evaluate mediated modes of learning in natural environments, involving children and teenag- ers in the Azores. The FG project seeks to provide learning opportunities whilst offering local audiences interactive learning experiences in nature-rich environments through the design of a mobile app created specifically for the project [18]. Rather than opting for “off-the-shelf” content, or generating content a priori for a local audience, we designed this study to better understand if and how biodiversity interests local children and teenagers. In the process, we tested the cultural probe technique, commonly used in qualitative research, and which remains underexplored within the EE literature. The cultural probe technique Design researchers Gaver, Dunne and Pacenti [19] first introduced CP as a qualitative data- gathering technique used to generate inspirational responses in the context of project briefs that aim to design new artifacts. As a research technique, CP "rely on participants’ self-docu- mentation" [20], i.e., information that is, upon consent, later shared with a research team for making sense of the data. For example, in one study [21], researchers used CP to explore "how people live at home" and to ultimately help design researchers "shake the preconceptions" they might hold about the topic. Toward this aim, the same study presented participants with "a dis- posable camera repackaged with requests for specific pictures" of the home, along with a

“friends and family map” to encourage participants to “diagram family relationships”. The study also presented a “Dream Recorder” to facilitate the recording of dreams upon awaken- ing. Data retrieved from CP packages, such as the one described above, often originate subjec- tive interpretation of activities reflecting personal responses arising from participants’ involvement in research. As detailed above, the CP technique often entails creating packages that present participants with a series of evocative tasks. Packages typically contain maps, postcards, disposable cameras, diaries, and other familiar objects selected for exploring a given context. Thoring et al. [22] present commonly used probe items devised for a CP package, such as a blank notebook for participants to record “observations and ideas”. Maps are also widely used to “structure a given space” where probe activity might occur. The authors also mention “frameworks”, items that help “structure” probe related activities but that are meant for participants to “fill with their ideas or observations” such as “mind maps”, “concept maps”, or “postcards”, to name a few possible examples. Items that capture visual evidence, e.g., through video or photo docu- mentation, are also relevant, along with physical materials that participants can use to develop ideas, depending on the nature of the project. While clear instructions accompany most probe items, researchers might find it helpful to add “random probes” through which participants can “decide (for) themselves what to docu-

ment and when”. Akin to quantitative research methods and despite the qualitative nature of the CP technique, the authors also advocate the use of questionnaires and surveys as comple- ments. Finally, “supporting material” in the form of pens and paper is also valuable. At the same time, the inclusion of a “gift” can help make a cultural probe package more compelling and help further encourage participation. The authors [22] further present probe items according to their function and advise those wishing to use the technique to consider creating or selecting items according to six categories. These include: (1) document observations and activities; (2) envision ideas, wishes, emotions, visions; (3) inspire participation in cultural probe related activity or provide inspiration for the completion of an activity; (4) motivate participation; (5) instruct or explain how probes could or should be used; and (6) items which support a practical function, such as a pen and paper. PLOS ONE Cultural probes for environmental education PLOS ONE | https://doi.org/10.1371/journal.pone.0262853 February 10, 2022 3 / 30

Whether researchers attribute one or more functions to an item, the authors see the CP tech- nique as an opportunity to stimulate “empathy”, “closeness”, “discussion” and “collaboration” between researchers and participants. CP should also support degrees of “playfulness”, “fun” and “engagement” along with the completion tasks or activities. In the context of design-led research, Thoring et al. [22] present CP and their potential in: providing "a deeper understanding of a given theme", "making the invisible visible", "inspire design", "foster creativity", and "engender interpretation". Such advantages position CP within a qualitative approach that, at times, can pose challenges as well. As a result, the authors also highlight obstacles encountered in the CP literature. While their list is exten- sive, here we provide seven challenges that we believe best encapsulate work with CP in the context of EE, namely: "1) finding a balance between information and inspiration, 2) acknowledging uncertainty and ambiguity of probe results, 3) no guarantee for a "hit" with the participants, 4) time for creating a good probe, 5) time for interpreting rich data, 6) par- ticipants perceiving probe use as another "job", and (7) “asking in a way that gives you already answers that you know". Inquiry-based learning EEM should not only convey information, but they also “should build lifelong skills that enable learners to address environmental issues” and that emphasize creative thinking skills, such as the formulation of new questions [4]. From this pedagogical perspective, our use of the CP

technique in this study is grounded in inquiry-based learning (IBL), since it was our intention to use the CP to elicit responses from participants through questioning. Informed by a constructivist approach, IBL has mostly impacted the learning sciences with positive implications for environmental education [23, 24]. The ’learning-through-questions’ that forms the core of this approach is particularly valuable. For example, the work of King [25] demonstrates that question-based learning strategies are beneficial in developing critical- thinking and learner autonomy. Concerning learner autonomy, the author notes that “self- generated elaborations have been found to be more conducive to learning then elaborations provided by a teacher, textbook or other external source”. As detailed in the work of Nappi [26], as in the work of King [25], the rationale behind inquiry-based learning, which draws on a Socratic tradition, positions the act of questioning, individually or among peers, as a tool with the potential to prompt a learner to think in new ways and to connect new understand- ings with existing knowledge. Such a process has implications for developing higher levels of thinking [26] and can yield in greater use of logical and deductive reasoning. Of relevance for the FG project is the argument by Nappi that questioning is essential for our capacity to “make sense of the surrounding world”—a foundational attribute of environmental consciousness [27]. We are accustomed to questioning in science education [28]. However, it is essential to

reinforce that ecological literacy also benefits from question-based approaches. For example, the work of Braus and Wood [23] state that "to produce a world of critical and creative thinkers that can help solve environmental problems, we need to encourage students to ask questions and think critically". Similarly, the work of Tolppanen and Aksela [24] highlights the impor- tance of learners’ questions when teaching about climate change. These examples support the idea that environmental education benefits from a learner’s questioning approach. And yet we must distinguish inquiry-based learning from the simple act of questioning, as IBL requires a sustained and reasoned approach to formulating questions [29]. Nonetheless, the IBL literature provides an important pedagogical framework for the design of the toolkit devised for this study. PLOS ONE Cultural probes for environmental education PLOS ONE | https://doi.org/10.1371/journal.pone.0262853 February 10, 2022 4 / 30

The senses, emotion and aesthetic experience in EE In our use of the CP technique, we also considered the work of Sauve´ [30], which identifies 15 currents of intervention in EE. As suggested by the author, these currents are not isolated from one another, and often initiatives will combine the different perspectives outlined in each. What stands out in Sauve´’s review is not only the already established value of cognitive and affective modes of learning, but also the growing importance of sensorial, experiential (e.g., through direct contact with nature), creative (or aesthetic) experiences in EE. Such values reflect the impact of postmodern thought in education and research more broadly, resonating with Lyotard’s view that knowledge is best understood when subjective human experience is equally contemplated [31]. While referencing the work of Jickling [32], Sauve´ [30] highlights a perspective of EE that values “sensual experience, sentiments, and emotions, as a way of reconnecting with the rest of the world”. This perspective attunes to more recent work that demonstrates the value of learn- ing in and with the “multisensory richness of landscapes” [27], and of “sensations, perceptions and feelings evoked by aesthetic experiences” in specific biomes [33]. Research questions In describing in greater detail the CP technique, IBL and EE’s focus on sensory, emotional, and aesthetic experience, we designed this study with the view of presenting the CP technique to those wishing to generate context-specific materials that engage children and teenagers with

biodiversity [7]. In so doing, we demonstrate that CP are not only valid in engaging partici- pants with nature-rich environments through questioning, the technique can also be effective in engaging participants in rich sensory, emotional, and aesthetic ways. Given that when work- ing directly with specific communities (such as island residents) "content should emerge from and address (their) needs" [6], we hypothesize that CP can facilitate the adoption of a participa- tory approach to the development of topics of interest in conversation with children and teen- agers. In addition—and serving as the focus of this study—CP can at the same time provide a meaningful and contextually relevant experience with and in nature. As a result, we formulated the following research questions: RQ1: Can the CP technique instigate productive questions regarding the surrounding natural environment on behalf of participants? RQ2: Can CP provide an outdoor learning experience that taps into the value of sensory, emo- tional, and aesthetic experiences in and with nature? RQ3: Can CP promote participants’ engagement and satisfaction with the activities and with the exploration of nature-rich environments? Methodology Context Study setting. On the 1st and 7th of December 2019, as part of the activity ‘Rediscovering Nature’, we performed two visits to the trail of Miste´rios Negros, located in the Nature Park of Terceira. We chose a trail in a protected area (Natural Reserve of Serra de Santa Ba´rbara and Miste´r-

ios Negros) that would expose participants to native, endemic, and exotic species (Fig 1). Native species arrived in the Azores through long-distance dispersal and therefore exist in other island and continental habitats. In contrast, Azorean endemic species (or subspecies) PLOS ONE Cultural probes for environmental education PLOS ONE | https://doi.org/10.1371/journal.pone.0262853 February 10, 2022 5 / 30

occur only in the Azores, resulting in either speciation events (neo-endemics) or extinction of the mainland/source populations (paleo-endemics) [10]. The trail also includes exotic species (e.g., Cryptomeria japonica), introduced by humans [34]. Some of these species are now classi- fied as invasive (e.g., Hedychium gardnerianum) due to their proliferation rate, high abun- dance cover and negative impacts. Participants. We recruited participants, ages 10 to 18, through the help of two local Scouts groups. Participants and their caretakers accessed information and consent forms via their respective Scouts group. Children and teenagers willingly participated in the study, and we informed them that we might request their participation during a post-trail activity. We also reported to them that they could withdraw their participation at any time. For this study, we obtained ethical approval from the Research Ethics Committee of the University of the Azores. A total of 36 participants (19 female and 17 male) participated in visits to the trail, coming from both councils of Terceira Island, Angra do Heroı´smo (Santa Ba´rbara) and Praia da Vito´- ria (Lajes). Considering the islands’ small area (400 km2), all residents are relatively close to the Natural Park, less than a half an hour ride, although there is no public transportation for these locations. Of all participants, 23 Scouts were between the ages of 10 and 14, and 13 were Fig 1. Natural Reserve of Serra de Santa Ba´rbara and Miste´rios Negros—Terceira’s Nature Park. https://doi.org/10.1371/journal.pone.0262853.g001

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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

Secondly, we assessed the efficacy of the technique in promoting sensory, emotional, and aesthetic experiences in nature-rich environments by looking at the frequency with which par- ticipants, in the final free, open-ended activity, focused their responses on qualities experi- enced during the trail walk (e.g., concerning a specific location, a moment, a feeling, etc.). Finally, we assessed participants’ engagement with a nature-rich environment by analyzing: the observations registered by adult volunteers during the trail walk; the participants’ evalua- tive judgments expressed in the final free, open-ended activity (to assess their degree of moti- vation and satisfaction with the trail walk); and participants’ willingness and motivation to return to the trail. The field guide cultural probe toolkit. Figs 2, 3, 4 and 5 present the FG cultural probe toolkit with signs demarcating station points along the nature trail. Figs 3 and 4 show a cotton canvas bag that was specially designed for the project to contain and transport probe items. We divided the first two kilometers of the trail into 12 demarcated stations and added beginning (Station 1) and endpoints (Station 14) to provide an opportunity to understand par- ticipants’ impressions of the surrounding environment. At the beginning of the trail, partici- pants were invited to perform a free-word association exercise in response to a given sentence; at the end, participants were asked to briefly close their eyes for a moment and then write

down any words that came to mind (Table 2). In line with Thoring et al. [22], we designed both beginning and end stations for documentation, inspiration and motivation. Stations 2 to 13 bore a title expressed with a single word or short phrase (Table 2, in bold). As in Gaver et al. [19, 21], we intentionally thought of creating signage as a means of defining specific locations on the trail and eliciting curiosity, therefore aligning with Thoring et al. [22] with respect to the of capacity CP to inspire participants. In each station participants were asked to engage with a specific activity designed to both inspire interaction with nature and instruct on the activity itself. As shown in Fig 4, the toolkit bag contained practical items, such as an A5 clipboard, three pencils, an envelope with a pencil sharpener and an eraser, a cord for completing the ’Create your park’ activity, and a trash bag for the ’Help the forest’ activity. We provided activity sheets for each station to document participants’ responses to activities when relevant, and to inspire interaction with the surrounding environment. We also included one mobile phone per group with a protective pouch to document the ’Create your park’, ’Who lives here?’ and ’Lime- Green-Bud-Green’ activities. A set of wooden tokens (Fig 5) featuring the content-free ques- tions served the purpose of motivating participants to ask questions and instructing them on possible types of questions. In line with the inquiry-based educational literature that emphasizes the positive benefits of

devising support strategies for question-based learning [37], we designed nine medium-den- sity tokens, laser-printed on fiberboard (Fig 5) and etched with a content-free question (Table 3). Our intention was to facilitate the formulation of participant questions through con- tent free questions. Nine of the 10 content-free questions draw on King [38], as translated to Portuguese. However, we excluded one of King’s questions—"How does . . . tie in with . . .. that we learned before", given the lack of a formal learning activity prior to the visiting the trail. Participants also had access to an additional question sheet for each station, except for the start and endpoints. With this sheet, we hoped to document the questions formulated by participat- ing groups with the help of the tokens. While we employed an IBL strategy in the design of question tokens, the toolkit was designed to explicitly evoke sensory experiences by inviting participants to attune their senses to nature through sensation such as touch, feel, squeeze, smell, and hear, as indicated in Activi- ties 2, 3, 8, and 11 (Table 2). With respect to emotion, station titles, such as ’Help the forest’, were intended to elicit in participants a sense of care for nature. Instructions asking PLOS ONE Cultural probes for environmental education PLOS ONE | https://doi.org/10.1371/journal.pone.0262853 February 10, 2022 8 / 30

Fig 2. Station sign displaying the original Portuguese title ‘Viaja no Tempo’ (‘Travel in Time’). https://doi.org/10.1371/journal.pone.0262853.g002 PLOS ONE Cultural probes for environmental education PLOS ONE | https://doi.org/10.1371/journal.pone.0262853 February 10, 2022 9 / 30

participants to pause, be silent, hear, smell, touch, visually admire different natural elements were designed to encourage an aesthetic experience. We also invited participants to engage introspectively with nature while reading a poem by Alberto Caeiro (one of Fernando Pessoa’s heteronyms) [39] in Activity 11 (Table 2). Individual stations additionally provided more Fig 3. The Field Guide cultural probe toolkit canvas bag (with original project title in Portuguese). https://doi.org/10.1371/journal.pone.0262853.g003 PLOS ONE Cultural probes for environmental education PLOS ONE | https://doi.org/10.1371/journal.pone.0262853 February 10, 2022 10 / 30

standard information regarding local nature conservation. See, for example, Activity 4, ’Help the forest’ (Table 2), where we present the kahili ginger (Hedychium gardnerianum), an inva- sive species that poses a significant threat to biodiversity in the Azores [40]. Fig 4. Toolkit bag contents. https://doi.org/10.1371/journal.pone.0262853.g004 PLOS ONE Cultural probes for environmental education PLOS ONE | https://doi.org/10.1371/journal.pone.0262853 February 10, 2022 11 / 30

To summarize, in Table 4, we present the FG CP toolkit according to the categories and functions described by Thoring et al. [22]. Procedure. We performed two visits on the 1st and 7th of December 2019. In the first visit, we welcomed 15 participants (eight between the ages of 10–14 and seven between 15–18). In the second visit, we welcomed 21 participants (15 between the ages of 10–14 and six between 15–18). Due to the length of the trail, the level of difficulty, and the time needed to cover the ter- rain, younger participants (ages 10–14) visited Stations 2 to 7, the older participants (ages 15– 18) visited Stations 8 to 13, this in addition to Station 1 and 14 which both groups visited. Before initiating the trail activity, we asked participants to perform a free-word association exercise in response to the sentence (here translated from Portuguese): "Write freely the words that come to mind when you think of ’natural forests of the Azores´´´. With this exercise, we wanted to gauge participants’ impressions of the local natural environment we were about to visit. At the end of the trail, we asked participants to close their eyes for a moment and then write down any words that came to mind. Fig 5. Question tokens (with questions in Portuguese). https://doi.org/10.1371/journal.pone.0262853.g005 PLOS ONE Cultural probes for environmental education PLOS ONE | https://doi.org/10.1371/journal.pone.0262853 February 10, 2022 12 / 30

With the support of 10 adult volunteers during both visits, we welcomed participants to the starting point where they established themselves into groups of two or three members. We fol- lowed with an explanation of the activity. Group members were encouraged to adopt different Table 2. Station titles and their corresponding activities. Station 1. Take a break. Before we start our walk, close your eyes for a moment and then write the words that come to mind. Station 2. The mystery of water. Squeeze these two plants (moss and Japanese cedar) and measure the resulting volume of water. Observe the differences. Station 3. The smells of the forest. Identify as many smells as you can. Indicate the ones you dislike as well as the ones you like the most. Station 4. Help the forest. This plant is one of the invasive species that takes up most space from the original plants of the Azores. You can help control this problem by pulling out a plant or, by removing all the leaves. Station 5. Create your park. Use the cord provided in your pack to delimit an area (‘reserve’) that contains what you think is most important to keep. Photograph your ‘reserve’, give it a name, and record the time when the corresponding photo was taken. Station 6. Who lives here? Select the three species that you consider to be most characteristic of this site and photograph them. Discuss the reasons why you chose these species and what you know, or would like to know, about each one. Station 7. Where am I? Discuss and record your answer.

Station 8. Touch and feel. Describe everything you feel as you touch mosses, ferns, and tree trunks. Station 9. Manager for 10 min. Identify 4 elements that exist in this lagoon. Of those that do not exist, choose the ones you would like to see here while referring to what would change with their introduction to the lagoon. Station 10. Where are the animals? Look for animals on various substrates: air, water, soil, bark, etc. List them and quantify them. Station 11. Hear the Forest. Be silent until you hear the bell and make a list of the sounds you identified. List: (1) what you heard; (2) what you heard and were not expecting to hear; (3) what you were waiting to hear and did not hear. Now read the poem below by Alberto Caeiro (here translated by the leading author from the original version in Portuguese): That lady has a piano Which is nice but it’s not the running of rivers Nor the murmur the trees make. . . What do you need a piano for? It’s best to have ears And love nature. Station 12. Lime-Green-Bud-Green. Take photographs of the different shades of green you see here. Now imagine what this landscape would look like without some of these shades. What if you could only see one shade of green here? Discuss these questions. Station 13. Travel in time. Imagine going back 250 years in time. You are in the year 1769, eight years after the eruption of Miste´rios Negros in 1761. Describe what was here at the time. Now travel 250 years into the future. You are in the year 2269. Describe what you see.

Station 14. Close your eyes. We have reached the end of our walk. Once again, close your eyes for a moment and then write the words that come to mind. . . https://doi.org/10.1371/journal.pone.0262853.t002 Table 3. Content-free questions. 1. Describe . . . in your own words. 2. What does . . . mean? 3. Why is . . . important? 4. Explain why . . . 5. Explain how . . . 6. How are . . .. and . . .. similar? 7. ’’How do. . . and. . . differ?’’. 8. How could . . . be used to . . .? 9. What would happen if . . .? https://doi.org/10.1371/journal.pone.0262853.t003 PLOS ONE Cultural probes for environmental education PLOS ONE | https://doi.org/10.1371/journal.pone.0262853 February 10, 2022 13 / 30

roles, such as note-taking, transportation of the canvas bag, transport, and mobile phone use, while it was explained that the posing of question prompts was a group task. At this point, we also presented the canvas bag and its contents. It is important to note that adult volunteers contributed alongside the research team in the form of structured notetaking, involving: (1) sensory impressions, (2) observations regarding interaction and communication, and (3) any additional notes. For the sensory impressions cat- egory, we looked for data relating to participants’ mood in each station (excitement, boredom, etc.). For the interaction and communication category, our focus was on the interaction between participants in each group. For example, how did participants delegate tasks and share resources? Was there a good synergy between group members? Was anyone left out? For the additional notes category, we asked volunteers and participating team members to record extracts of sentences or conversations uttered between participants. Data analysis. We transcribed data collected during the trail walk and the post-trail activ- ity using Microsoft Excel software to synthesize and categorize data. A thematic analysis of the data was necessary to define the categories of the indicators (type of approach to the task of questioning, focus of the motives to return to the trail, dominant theme of the final responses; and degree of the evaluative judgements of the final responses). Themes were developed a pos-

teriori, without a pre-existing categorization system. This inductive process included all responses collected over the two visits. We expand on the operationalizations of the different categories in the Findings section. To ensure the interpretation and validity of the results, we used several quality processes, namely: 1. Triangulation: two researchers with different academic backgrounds (one with an MS in Biology and one with a PhD in Psychology) performed the analysis. 2. Intercoder reliability test: a Cohen’s kappa coefficient was calculated in a random sample of 35 of the 237 units of meaning, categorized independently by four judges, and re-calculated after redefining categories to solve disagreements and until we reached a near-perfect agree- ment result (0.98). 3. Iterative data processing: performed to include all relevant information from participants as well as accommodate new refinements of the classification system for the only category that resulted in an initial poor agreement kappa coefficient (0.20; "type of approach in the task of questioning" category). Table 4. Field Guide cultural probe toolkit, according to the categories and functions described by Thoring et al. [22]. Item Category Function Station signs Maps Inspire, Instruct Cotton canvas bag Wrapping Practical Activity sheets Frameworks Inspire, Instruct, Motivate Question sheets Frameworks Document Content-free question tokens Frameworks Instruct, Visionary Mobile phone Photo/ Video Documentation Document Drawing board, three pencils, pencil sharpener, and eraser

Supporting Material Document Cord, trash bag Supporting Material Practical, Motivational https://doi.org/10.1371/journal.pone.0262853.t004 PLOS ONE Cultural probes for environmental education PLOS ONE | https://doi.org/10.1371/journal.pone.0262853 February 10, 2022 14 / 30

To analyze participants’ degree of satisfaction with the trail walk, we also submitted their responses to the final free, open-ended activity to a similarity analysis of the semantic field. After translating the responses from Portuguese to English, we used the freeware program IRAMUTEQ [41] that produces a maximum tree of words by grouping the words and expres- sions into communities and interconnecting the communities to each other according to the frequency of evocations and the number of co-occurrences [42]. To explore differences between age groups, we performed Pearson’s Chi-square tests (χ2), with a 95% confidence level (p � .05), using the IBM SPSS Statistics for Windows software Version 27 [43]. When verified that more than 20% of expected frequencies were below five; we used the likelihood ratio value (G2) to replace Pearson’s Chi-square value (χ2). Findings RQ1 • Can the CP technique instigate productive questions regarding the surrounding natural environment on behalf of participants? By the end of the trail walk, we retrieved 168 questions. Four were incomplete, making it impossible to categorize them. From the remaining 164 valid questions, 137 were found to be sufficiently distinctive, indicating a high level of diversity of questions posed. Following an inductive process, we analyzed questions with respect to their related activity and the supervi- sor’s comments concerning participants performance in each activity. As a result, we were able to rank valid questions as either ’productive’ or ’strategic’.

The ’strategic’ category corresponds to questions triggered by the invitation to complete the study’s tasks or by design of the activity itself. In these cases, participants overlooked the opportunity to obtain new information through questioning by deriving questions based on those presented on the tokens. For example, we received the question "Describe the sounds of nature", which is similar to the question posed to participants during the activity at Station 11: "(. . .) make a list of the sounds you identified". Note that our use of the term ’strategic’ differs from King’s [25], who in one study used the word to define questions "used by students to guide their planning and monitoring activity during problem solving". In the ’productive’ category, we included internally oriented questions triggered by the desire to question and obtain knowledge or confirm previous knowledge related to the external context. This category comprises externally oriented questions triggered by participants’ exploration of the external context, such as the natural context, or the previously performed activities. In either context, ’productive’ questions are those that refer to a genuine interest in knowing more. An example of an internally oriented question is "Why is biodiversity important?" which does not directly accrue from the activity performed in Station 3 ("The smells of the forest"). Also, a comment from the station supervisor suggests that the group who produced this ques- tion was suitably motivated ("They are doing the work with certain dedication."). An example

of an externally oriented question is ‘‘How could the water from the lagoon be used?”, which, although it does not directly relate to the corresponding activity, relates to the natural context of Station 10 (‘‘Where are the animals?”), where it was produced. Note that this station was also near the lagoon that can be found in Miste´rios Negros (Fig 6). From the 164 valid questions, nine-tenths (89%; n = 146) were found to be ‘productive’, while nearly all the questions were externally oriented (94%; n = 137), focusing on the immedi- ate natural context or performed activities. Only 11% (n = 18) were categorized as ‘strategic’ PLOS ONE Cultural probes for environmental education PLOS ONE | https://doi.org/10.1371/journal.pone.0262853 February 10, 2022 15 / 30

Fig 6. One participant touches water of the lagoon that can be found on the trail. https://doi.org/10.1371/journal.pone.0262853.g006 PLOS ONE Cultural probes for environmental education PLOS ONE | https://doi.org/10.1371/journal.pone.0262853 February 10, 2022 16 / 30

questions (Fig 7). The collected data suggest that the CP technique promoted productive ques- tioning concerning the surrounding nature-rich environment. Overall, differences between age groups are significant (χ2(1) = 5.839; p = .016), and the number of ’strategic’ questions is much smaller in the older group. Nonetheless, both groups generated a higher number of ’productive’ questions; 84% (78 out of 93) for the younger par- ticipants, 96% (68 out of 71) for the older participants. Additionally, we crossed the questions posed with their corresponding activities to determine whether some activities prompted more ’strategic’ questions than others. For the younger participants (Fig 8), the distribution of ’productive’ and ’strategic’ questions by activity is not homogenous (χ2(5) = 12.666; p = .027). Activities 3 ("The smells of the forest") and 6 ("Who lives here?") raised a more significant number of ’strategic’ questions when compared to other activities. For the older group (Fig 9), ‘strategic’ questions represent only three out of 71, corresponding to just two activities. Thus, the distribution of ‘productive’ and ‘strategic’ questions was not significantly different between activities (χ2(5) = 7.541; p = .183). When distributing questions by question tokens used in their production (Fig 10), we observed that participants used all of the tokens provided. However, their selection is not homogenous; it is evident that the tokens ‘‘Explain why. . .?” (27%; n = 44) and ‘‘Why is. . .

important?” (21%; n = 34) were preferred. In the first token, the focus is on possible causes– e.g., ‘‘Explain why invasive plants exist?”–and the purpose of something–e.g., ‘‘Explain why nature needs moss, fern and trees?”. In the second token, the focus is on the relevance of the purpose–e.g., ‘‘Why is preserving nature important?”. Tokens related to comparison, e.g., "How are. . . and. . . similar" and "How do. . . and. . . dif- fer", as well as those associated with the utility of something, e.g., "How could. . . be used to. . .?" were used less often. We further observed that only 7% of the questions (n = 11) were constructed without the use of tokens–e.g., "Do plants choose their natural environment?". Thus, content-free question tokens appear to benefit participants’ questioning. Additionally, the distribution of ’productive’ and ’strategic’ questions is significantly different between Fig 7. Distribution of valid participant questions (n = 164) according to the approach adopted in questioning by age group. In total, younger participants generated 93 questions, and older participants generated 71 questions. https://doi.org/10.1371/journal.pone.0262853.g007 PLOS ONE Cultural probes for environmental education PLOS ONE | https://doi.org/10.1371/journal.pone.0262853 February 10, 2022 17 / 30

question tokens (χ2(9) = 51,828; p < .001). The token "Describe. . . in your own words" pro- moted more ’strategic’ questions than the other tokens. Three-quarters (12 in 16) of the ques- tions produced with this token were found to be ’strategic’, possibly owing to the descriptive nature of the token that encourages the production of questions by adding just one noun. RQ2 • Can CP provide an outdoor learning experience that taps into the value of sensory, emo- tional, and aesthetic experiences in and with nature? From the last free, open-ended activity, we retrieved 34 responses (two participants did not respond), which were then translated from Portuguese to English. From the analysis, we observed that 22 participants responded with free-word associations (e.g., ‘‘silence, singing, birds”) and 12 with phrases (e.g., ‘‘This journey was magnificent with beautiful plants and landscapes”). We categorized all 34 responses according to their "dominant theme", or the main idea expressed when attributing meaning to the experience. Responses highlight participants’ per- spectives that arise from features of the activity, with our interpretation of the "dominant theme" closely following Litfin’s [44] definition of a "frame" of an object or phenomenon. Fol- lowing an inductive process, and after analyzing all possible answers, we identified three main thematic categories. We infer that participants focused their responses on one of the following: