Apart from the technological challenges connected to lockdowns and remote working, the COVID19 pandemic has brought with it also the importance of caring for nature and the importance of environmental awareness. This coincides with what is encompassed in the United Nations’ Sustainable Development Goals (SDGs) ^[1], where several of the sections refer to the importance of sustainability and environmental awareness. However, the current use of technology in education is quite disconnected from the goal of environmental awareness and especially the protection of flora and fauna. The possible lack of a relationship between technology and plants means that the blending of both disciplines is sometimes difficult to find and has been severely underexplored.

Plants can play two different roles in learning activities: (a) a primary role, where plants are used during the learning activity (foreground); or (b) a secondary role, where plants do not intervene in the learning activity (background). This  classifies learning activities where plants had a primary role. Therefore, studies investigating the effects of plants in the classroom where plants were not a deliberate object of attention during the learning activity, but rather the subject of an independently performed research, were discarded (e.g., the impact of plants on psychological ^[2] or environmental aspects ^[3]).

On the technological side, researchers have tried to bring together new trends in the use of technologies in education, as can be seen in the 2022 EDUCAUSE Horizon Report by Pelletier et al. ^[4]. Thus, education is relying on emergent technologies to provide a better classroom experience [5,6]^[5][6]; among others, Internet of Things (IoT), learning analytics, artificial intelligence, virtual reality, augmented reality, and blockchain are trending educational technologies ^[4].

One of the emerging technologies that favors the creation of smart learning environments is IoT, which enable learning environments and learners to take advantage of features such as hypersituation ^[7] or student tracking ^[8]. Additionally, microcontroller and sensor programming learning activities are becoming more frequent [9,10,11]^[9][10][11] (thus promoting IoT), and the number of articles, conferences, and journals published on this topic has increased in recent years. However, education is not only taking advantage of IoT and its features to move towards smart learning spaces. There are meta-reviews that examine how other types of technologies have been used in education: big data ^[12], virtual reality ^[13], learning analytics ^[14], artificial intelligence ^[15], and blockchain ^[16].

While research into emergent learning technologies is thriving, the use of technology for learning about the natural environment or plants and their properties is not sufficiently explored in the scientific literature. The studies and reviews mentioned above do not focus on the field of botany and environmental awareness, but give an overview applied to all areas of education, bringing together all disciplines covered by education. This could represent a gap in the current research, given that there are technologies that can be applied specifically to a single subject such as biology and which better explore its characteristics.

2. Education Level

Learning activities were classified considering the education level at which they were developed. The results show that ‘Secondary school’ [21,23,25,27,28,30,31,33,34]^{[17][18][19][20][21][22][23][24][25]} was the educational level at which most learning activities were conducted (64.29%), followed by ‘Primary school’ (50%) [22,24,26,29,30,32,34]^{[22][25][26][27][28][29][30]}, and ‘Tertiary school’ [28]^[21]. Some learning activities were conducted [28,30,34]^[21][22][25] with students from two different educational levels. With regard to secondary school levels, Southgate, E. et al. [21]^[17] conducted a virtual reality group activity (in groups of 3) in which 54 secondary school students participated. In the activity, they used immersive augmented reality with the Oculus Rift device in the videogame Minecraft to build a model of a plant to demonstrate their knowledge and understanding of different concepts related to plants such as respiration and photosynthesis. For this learning activity, they used a virtual species of Hyacinthoides (genre). With regard to primary school levels, Liu, W. et al. [32]^[30] prepared an individual mixed reality (MR) learning activity in which 40 primary school students used the tool Plant Mixed Reality System (PMRS) to interact in a virtual environment with objects that could be picked up and moved. Students were able to perform different actions and explore key processes in a configurable virtual environment using a virtual plant: seed germination, seed disposal, photosynthesis, and reproduction. The virtual environment was touchless (without keyboard or mouse). The PMRS was intended to understand students’ acceptance of the mixed reality (MR) technology for learning, and the factors pertinent to influence their intention to use it. In addition, a quiz was included in the system to measure “entertainment” factors and to evaluate the system. The PMRS was considered interactive, enjoyable, interesting, and engaging. With regard to mixed school levels, Silva, H. et al. [28]^[21] carried out a group activity (2 students per group) in which a total of 296 secondary school and tertiary school (247 tertiary and 49 secondary) students participated. In the activity they were asked to use a tool known as ‘Interactive Dichotomous Key (IDK)’. This software assists in plant identification by formulating specific questions: type of reproductive structures, ovary position, connection of floral parts, insertion and shape of the leaves, among others. The authors conclude that the development of multimedia tools such as the IDK can be a simple and effective solution to increase the motivation of students and teachers to study plant-related science. For this learning activity, the researchers used the species Clematis campaniflora, Papaver rhoeas, and Ranunculus repens. In the selected studies, tertiary school students are an audience with whom almost no plant-based learning activities involving technology are conducted. Due to the scarcity of papers from tertiary level, researchers are left with speculation as to why this is not occurring. Perhaps the reason for this is that they are already experienced students, and they have a knowledge level where such activities are felt to be inappropriate. Perhaps lecturers find it more appropriate to teach them at an abstract theoretical level. However, researchers should work on innovative learning activity templates to be able to train tertiary students on direct interactions with real natural environments and plant habitats to provide them with new insights through innovative ways of teaching/learning involving plants.

3. Pedagogical Approach

This section classifies the pedagogical approach considered in each learning activity as cited by the authors of the articles reviewed. The most frequently cited pedagogical approaches were mobile learning (28.57%) [22,26,30^{[22][24][26][28]},33], inquiry-based learning [27^[20][24][25],33,34], and collaborative learning [21,27]^[17][20]. In addition, some articles describe learning activities related to augmented-reality learning [24]^[27], classroom teaching [32]^[30], edutainment [32]^[30], e-learning [28]^[21], self-learning [32]^[30], and video learning [24]^[27]. The rest of the authors (35.71%) did not specify the type of pedagogical approach that the learning activity they have performed had [23,25,29,31,34]^{[18][19][23][25][29]}. With regard to mobile learning, Umer, M. et al. [33]^[24] conducted an outdoor group activity (4 students) in which 42 secondary school students participated in a unique intervention. Before the outdoor activity, they were asked to do a previous work to understand different concepts related to plants found in the school garden and insert data in an application. Later, they were asked to consult a marker that was placed in the plants with their cell phones that contained information related to the plant and related to the class syllabus. In addition, the application displayed a 3D model of the plant on the marker so that the students could consult information about different parts of the plant. Finally, students filled out a questionnaire and answered questions focused on the mobile learning experience and what they learned from the system. For this learning activity, they used the species Pinus sylvestris, Agaricus bisporus (fungus), Arecaceae (genre), and Lotus (genre). With regard to inquiry-based learning, activities are divided into the following phases [35]^[31]: ‘Orientation’, ‘Conceptualization’, ‘Investigation’, ‘Conclusion’ and ‘Discussion’. The authors have identified three articles that mention this type of learning [27,33,34]^[20][24][25], and the authors have been able to verify the phases of each one of them. The ‘Orientation’ phase is something that all the articles included [27,33,34]^[20][24][25]; none of them included the ‘Questioning’ phase; two of them included the ‘Hypothesis Generation’ phase [27,34]^[20][25]; all of them included the ‘Exploration’ phase, either planned by the students or the researchers [27,33,34]^[20][24][25]; two of them included the ‘Experimentation’ phase, either designed by the students or the researchers [27,34]^[20][25]; two of them included the ‘Data interpretation’ phase [27,33]^[20][24]; only one of them included the ‘Conclusion’ phase [27]^[20]; two of them included the ‘Communication’ phase [27,34]^[20][25]; and two of them included the ‘Reflection’ phase [27,33]^[20][24]. Although many activities try to innovate when it comes to using technology, some are based on traditional teaching methods but incorporate technology. Pinkerton, M. G. et al. [34]^[25] conducted an individual inquiry-based activity in which 730 primary and secondary school students participated during a unique intervention of 60 min. In the activity, they were asked to conduct a research paper on invasive species and plant biosecurity that they later had to present through self-prepared Powerpoint slides to explain what they had learned. The study was intended to increase the interest and awareness of Florida youth about invasive species so that they would learn concepts related to plant biosecurity and promote early detection of non-invasive species. The activity, divided into three parts (presentation, hands-on activity, and answering student questions), significantly increased the students’ understanding of invasive species and the importance of biosecurity. With regard to collaborative learning, Nantawanit, N. et al. [27]^[20] carried out an inquiry-based group activity (4–5 students per group) in which 31 secondary school students participated during a semester (6 interventions of 120 min). The activity consisted of several phases: engagement, experimentation, data discussion, active reading, and application, with the motivation of trying to dismantle the belief of many people that animals are more interesting than plants because plants are “passive living beings”.

4. Topic of the Learning Activity

All of the research papers reviewed focused on biology (100%) [21,22,23,24,25,26,27,28,29,30,31,32,33,34]^{[17][18][19][20][21][22][23][24][25][26][27][28][29][30]}. In addition, one of the articles also focused on the topic of mathematics [25]^[19] and another also focused on the topic of computer science [23]^[18]. With regard to activities focused on biology, Boudon, F. et al. [23]^[18] conducted an activity in which secondary school students participated over 35 weeks. In the activity, they were asked to use L-Py as a training tool in the classroom to construct the 3D plant structure of typical local plants. For this, the students first measured plants in the field, made diagrams, drew the plant architecture, and recorded the spatial distribution of the plants. For this learning activity, they used the species Euphorbia (genre). Very few of these activities have focused on the power of technology to obtain data about the plants themselves. Most of these activities have focused on the subject of biology, and some effort may be needed to get students to understand the ability of technology to obtain data on plants in an objective way. This seems to be related to the school curricula in which the study was conducted, as most of them were primary and secondary schools. At these educational levels, more importance is given to subjects such as biology or knowledge of the natural environment (with a broader and more generalist syllabus) than to others such as computer science (where the syllabus is sometimes reduced to office automation tasks).

5. Purpose of the Learning Activity

The purposes of the learning activities were classified considering the terms as cited by the authors of the articles and extracted from the reviewers in the data extraction process. The main purpose (92.86%) was to learn about plants, soil, water, and agricultural concepts [21,22,24,25,26,27,28,29,30,31,32,33,34]^{[17][19][20][21][22][23][24][25][26][27][28][29][30]} (92.86%). Likewise, learning activities (71.43%) were oriented to train digital competences [21,22,23,24,26,28,30,31,33,34]^{[17][18][21][22][23][24][25][26][27][28]}. In addition, some articles focused on learning scientific methods [23,29,31]^[18][23][29] or mathematical concepts [25]^[19]. With regard to the learn about plants, soil, water, and agricultural concepts purpose, Huang, Y.-M. et al. [26]^[28] carried out an outdoor mobile learning activity in which 32 primary school students participated. In the activity they were asked to use personal digital assistants (PDAs) with a Mobile Plant Learning System (MPLS) installed to get information about plants of the environment. With this activity, the researchers investigated the effectiveness of the system to learn about plants.

6. Educational Space Used to Perform the Learning Activity

Figure 1 shows that most learning activities (78.57%) were performed indoors [21,22^{[17][18][19][21][22][23][25][26][27][29][30]},23,24,25,28,29,30,31,32,34], whereas 42.86% were performed outdoors [22,26,28,29,30,33]^{[21][22][24][26][28][29]} (implying some kind of field study, i.e., learning activities in real/natural settings). Some activities (28.57%) combined indoor and outdoor spaces [22,28,29,30]^{[21][22][26][29]}. One learning activity was carried out in a hybrid mode [31]^[23]. Zacharia, Z. C. et al. [22]^[26] carried out a group activity (4 students per group) in which 48 primary school students participated over six weeks. In the activity they were asked to use smartphones to collect data about outdoor plants. With this, researchers wanted to find out whether using mobile devices to collect plant data improved learning over traditional (notebook and paper) data collection. Those students who used mobile devices were the only ones who were able to appreciate details such as the wind as a pollinating agent thanks to slow-motion recordings. Plant-learning activities have the advantage that their main object of study, plants, can be easily found anywhere. As such, these types of activities can provide an incentive for teachers to get students out of the classroom and experience different ways to learn about the environment through targeted field studies. However, depending on the type of activity and the level of education, this may mean that the teacher may need help from third parties or parental authorization. Therefore, a good option in primary schools is the use of indoor plants for students to learn while being in contact with nature. Another option is provided in school gardens and nearby parks.

7. Organization: Work-in-Groups or Individual

Students worked in groups [21,22,27,28,29,33]^{[17][20][21][24][26][29]} in 6 out of 14 learning activities (42.86%). There were three learning activities where students worked individually [30,32,34]^[22][25][30]. Two articles described learning activities combining the individual use of the technology within group settings [21,32]^[17][30]. Seven articles (50%) did not specify how students collaborated [23,24,25,26,31]^{[18][19][23][27][28]}. With regard to work-in-groups activities, Pressler, Y. et al. ^[29] conducted a group activity (2–4 students) in which primary school students were invited to participate in two experiments to explore the effects of biochar on plant growth and soil respiration. Students were invited to observe biochar and different soils through a microscope and different sensors (i.e., CO₂ and pH) and discuss properties such as porosity and pH and how these variables can affect the growth of a plant. For this learning activity, they used the species Vigna radiata. With regard to individual activities, Wang, C. [30]^[22] conducted an individual outdoor mobile learning activity in which 75 primary and secondary school students participated. In the activity, they were asked to participate in two outdoor mobile learning experiments using an Android application related to plant identification (204 different species) and learning about plants. With this, the researchers wanted to check if the use, learning attitude and interest in the natural sciences were greatly improved after the outdoor activities of plant identification and to explore the extensions that this system can have in different stages of primary school. For this learning activity, they used 204 species, but the authors did not specify what these species were. Six learning activities (42.86% of the total) involve groupwork. This could be due to several reasons, not necessarily a deliberate pedagogic design. In some instances, researchers may not have had enough technological resources for every student [33]^[24], so the students were put in groups. The shortage of technological resources in education centers is a widespread problem for institutions, and, equally, researchers cannot explore the use of technologies to the fullest. Therefore, the development of inexpensive technological systems that could support education should be considered.

8. Role of the Stakeholders

One the one hand, the role of the students during learning activities was mainly oriented to perform tasks related to the scientific method (collecting data, analyzing data, or reporting results) (85.71%) [21,22,23,25,26,27,28,29,30,31,32,34]^{[17][18][19][20][21][22][23][25][26][28][29][30]}. Students used technology to create digital content (i.e., using applications, building 3D models, and collecting data, photos or videos) (64.29%) [21,22,23,24,26,28,29,31,33]^{[17][18][21][23][24][26][27][28][29]} or to interact with the rest of stakeholders (i.e., communication, collaboration, and others) (50%) [21,22,25,26,27,31,34]^{[17][19][20][23][25][26][28]}. Students identified plants [26^[22][23][28],30,31], sometimes using laboratory resources to inspect plants (e.g., magnifying glasses) [22,34]^[25][26] or to take care of the plant ^[29]. On the other hand, the role of teachers in learning activities was oriented toward assisting students (i.e., suggesting resources based on their knowledge, providing feedback, facilitating materials, or guiding activities) (42.86%) [21^{[17][20][23][26][28][29]},22,26,27,29,31], performing management tasks (e.g., coordinating the learning activity) (28.57%) [21^{[17][25][28][29]},26,29,34], promoting activities related to scientific method [26,27]^[20][28] or being, primarily, a spotter [24]^[27]. Plant-related learning activities are not used solely to learn about plants, but they can also serve as a motive for students to interact with each other (and with others). Thus, the activities can be arranged as a “social activity”. However, relating this to the educational levels at which the research has been carried out, it is possible that this occurs because most activities have taken place in primary and secondary school, where this social factor is of great importance, while, on the other hand, such interactions among students has not been reported at the tertiary education level. In addition, the teacher linked to the students did not have a very prominent task within the learning activity. Most of their tasks had to do with supervising the work carried out and providing support where needed. A more active participation of the teacher could lead to higher motivation among the students, which would increase their involvement with the activity. The authors believe that the teacher, too, is a participant in the learning activities. Therefore, if the teacher adopts a passive role within the activities, this could result in a loss of opportunities to investigate new ways of carrying out learning activities or to encourage students’ interest.

9. Variables Observed

The following variables were observed in learning activities: (1) academic performance (64.29%) [21,22,24,26,27,28,29,31,34]^{[17][20][21][23][25][26][27][28][29]}; (2) aspects related to the learning process and its characteristics (learning satisfaction, focus, effectiveness, motivation, or students’ perceptions) (28.57%) [29,30,32,34]^{[22][25][29][30]}; (3) aspects related to the technology (acceptance of the tool, engagement of the technology, ease of use, and others) (28.57%) [21,28,30,32]^{[17][21][22][30]}; (4) critical thinking [21,29,31]^[17][23][29]; and (5) perceived environmental quality ^[29]. Some authors used pre-existing tests to observe and measure variables: Chang et al. [24]^[27] observed learning motivation in students using the test developed by Yang et al. [36]^[32]; Nantawanit et al. [27]^[20] used the Constructivist Learning Environment Survey (CLES) questionnaire developed by Salish [37]^[33] to measure learning performance; Pressler et al. ^[29] used Next Generation Science Standards (NGSS) [38]^[34] to measure learning performance. Some articles observed the technologies used: Liu et al. [32]^[30] measured technology acceptance [39]^[35]; Wang [30]^[22] used plant mobile learning applications test to measure location awareness [40]^[36]. Some of the evidence indicates that not all research focuses its efforts on transparency, since, although it is possible to deduce what variable is being studied in the research (such as academic performance or technology-related aspects), it is not always clear what type of protocol or tools the researchers have used to measure these factors. Although there is a possible increase of interest in the use of technology to teach about plants, there are no standardized questionnaires available to evaluate the different characteristics of these methods, other than questionnaires related to the engagement of the students produced by the use of these technologies.