Grand Challenges as Educational Innovations in Higher Education: A Scoping Review of the Literature

Grand challenges are complex problems that are common to much of society, affect large populations, and may have several possible solutions. Incorporation of grand challenges into higher education courses can facilitate the development of collaborative problem-solving skills while providing relevant and practical opportunities to experience the dynamics involved in real-world work. Although grand challenges are becoming more commonly used in higher education, to date, there has been no synthesis of how grand challenges are incorporated and the learning outcomes of engaging in grand challenge work. In this scoping review, we examined and mapped the state of evidence for the use of grand challenges in higher education. We conducted the review according to the Johanna Briggs Institute methodology for scoping reviews and considered quantitative, qualitative, and mixed-methods studies as well as literature reviews, program descriptions, and opinion papers published in English without limitations on year of publication. We used a data extraction tool to synthesize and present our findings in a tabular form with accompanying narrative summaries. The results reveal a growing global interest in the use of grand challenges in higher education while highlighting a lack of rigorous empirical evidence on the impact on student learning.


Introduction
Today's complex workplace environments demand higher education institutions to prepare graduates who are ready to tackle society's most pressing challenges. However, presentday education may not adequately prepare students for problem-solving approaches required of our modern workforce. Implementing grand challenges within higher education courses may help prepare students to engage in innovative solutions to complex problems.

Grand Challenges
e concept of grand challenges was first introduced by a German mathematician in 1900, who established 23 problems to foster dialog among mathematicians, spark the development of the discipline, and focus attention on unresolved issues [1]. Different from general disciplinary problems, grand challenges pose greater demands for coordinated and collaborative efforts [1], because they affect large populations, and cannot be effectively tackled by an individual organization, community, or discipline [2]. Fundamentally, grand challenges are global and common to much of society [1], which implies that their impact goes beyond a single discipline due to their complexity [2], longterm horizon, and wickedness [3]. Given the dynamic nature of grand challenges, it is difficult to develop simple solutions because they can take several years or decades to emerge and their impact may extend to future generations [4]. Grand challenges are often wicked in that they present large-scale common design problems that may have several possible solutions [2,5].

Societal Grand Challenges.
e distinctive feature of societal grand challenges is that they are highly significant and potentially solvable [6]. Societal grand challenges are phenomena with global impacts such as environmental and human health [7], global hunger, urban poverty [6], climate change, ageing societies, natural resources depletion, and gender inequality [1]. ese phenomena are common to various degrees across the world.

Addressing Grand Challenges.
Addressing a grand challenge requires inclusive leadership that actively seeks out the ideas and input of individuals within and outside the team. Including multiple perspectives provides a better understanding of the complex components of the problem and may lead to a contemporary solution. In business, collaboration among multiple team members from different departments is a common practice to produce solutions for product or service innovation [8]. Kania and Kramer [9] argued that "collective impact initiatives depend on a diverse group of stakeholders working together, not by requiring that all participants do the same thing, but by encouraging each participant to undertake the specific set of activities at which it excels in a way that supports and is coordinated with the actions of others" (p. 40). Such an inclusive approach is crucial considering that many of the most pressing global problems involve and impact individuals from multiple locations, professions, and worldviews.

Grand Challenges as Pedagogical Innovations.
Developing solutions to grand challenges as a pedagogical approach has resulted in deep learning for students [10]. Researchers found when instructors incorporated grand challenges into courses, it facilitated the development of collaborative problem-solving skills while providing relevant and practical opportunities to experience the dynamics involved in real-world work [11]. In the field of engineering, grand challenge courses have been designed to promote collaborative problem-solving skills where students need to tackle diverse engineering challenges and integrate ideas to generate a final solution which was highlighted as a critical component [12]. Promoting collaborative processes and involving multiple students to address grand challenges provided relevant and practical opportunities to experience the dynamics involved in the real-world work of an engineer [11].
Experiential learning such as grand challenge work that requires hands-on and applied learning opportunities can have a positive and powerful impact on the quality and meaning of learning experiences [13]. ere is sound pedagogical evidence for incorporating experiential approaches into higher education courses. Kuh's [14] influential research on high impact practices demonstrated that experiential learning experiences have a significant impact on students' overall academic success. Employers often seek job applicants with leadership, communication, and problemsolving skills that can be developed through well-designed and effective experiential learning opportunities [15]. As well, the emerging field of learning neuroscience supports experiential learning as being key to long-term memory acquisition [16]. As noted by Kolb and Kolb [17], "when a concrete experience is enriched by reflection, given meaning by thinking, and transformed by action, the new experience created becomes richer, broader, and deeper" (p. 309).
Although grand challenges are being more commonly used in higher education and have been implemented in several disciplines, Ferraro et al. [2] argued more research is needed to understand effective teaching strategies for carrying out grand challenge work, developing grand challenge solutions, and evaluating their impact. While there is emerging evidence that suggests engaging with grand challenges results in deep learning for students, the extent of evidence regarding the benefits of incorporating grand challenges into higher education learning opportunities has not yet been established. To date, there has been no synthesis of how grand challenges are incorporated and the learning outcomes of engaging in grand challenge work. e overarching objective of this review was to examine and map the state of evidence for the use of grand challenges in higher education. (1) In what contexts are grand challenges being used in higher education? (2) What learning objectives and assignments are used in higher education courses that incorporate grand challenges? (3) What types of outcomes have been reported in the literature related to the implementation of grand challenges in higher education classrooms? (4) What are the gaps in evidence for the use of grand challenges in higher education?

Design.
Various systematic approaches are available for reviewing published literature. Scoping reviews are a rigorous and methodical approach to examine the extent, range, and nature of research activity in a particular field. is scoping review was conducted in accordance with Joanna Briggs Institute (JBI) methodology for scoping reviews [18] and reported in accordance with the Preferred Reporting Items for Systematic Reviews and Meta-Analysis for Scoping Reviews Extensions for Scoping Reviews (PRISMA-ScR) [19].
is scoping review methodology guided us to broadly examine and comprehensively and systematically map the grand challenge literature, summarize research findings, and identify gaps where further research is required.

Eligibility Criteria.
For the purpose of this review, grand challenges were defined as complex problems that are common to much of society, affect large populations, and may have several possible solutions. Literature was eligible for inclusion if it focused on undergraduate or graduate students and/or instructors engaged in formal higher education settings where the application of grand challenges was integrated with or applied in the teaching and learning process to identify potential solutions. Primary research studies including qualitative, quantitative, and mixedmethods studies were eligible. In addition, literature reviews as well as text and opinion papers that met the inclusion criteria were considered. Only studies written in English were included due to difficulty in obtaining foreign language studies and the lack of language capabilities of the team.
We excluded dissertations, books, book chapters, book reviews, websites, and conference abstracts that did not include a full-text paper. Literature studies that focused on K-12 students or educators were also excluded. Literature studies that included grand challenges in higher education teaching and learning but did not attempt to identify a solution were also excluded.

Information Sources and Search Strategy.
We followed the JBI scoping review method which includes a three-step search strategy. First, an experienced health sciences librarian conducted an exploratory search of the truncated phrase "global challenge * " in a multidatabase search on the EBSCO platform. e four databases searched simultaneously included: Academic Search Complete, CINAHL, ERIC, and GeoRef. e exploratory search helped to identify key studies, relevant keywords in the titles and abstracts, as well as the subject headings.
is analysis informed the development of a draft search in ERIC, the prime education database. e draft search was piloted to ensure that all key studies were retrieved. e second step included finalizing the ERIC search strategy (Table 1), which was then adapted for all other databases, taking into account database syntax and thesaurus. In order to conduct a thorough investigation into grand challenges in postsecondary environments, both disciplinary and interdisciplinary databases were searched from inception until May 3, 2020. Disciplinary databases searched include the following:  TI (challenging N1 ("social problem * "or "global problem * "or "world problem * "))OR KW (challenging N1 ("social problem * "or"global problem * "or"world problem * "))OR AB (challenging N1 ("social problem * "or"global problem * "or"world problem * ")) 8 S3 TI "integrate module * "OR KW "integrate module * "OR AB "integrate module * " 4 S4 TI "big idea * "OR KW "big idea * "OR AB "big idea * " 486 S5 TI S13 TI (undergraduate * or graduate * or doctoral * or student * or professor * or instructor * or faculty or "preservice teacher * "or"pre-service teacher * ") OR KW (undergraduate * or graduate * or doctoral * or student * or professor * or instructor * or faculty or "preservice teacher * "or"pre-service teacher * ") OR AB (undergraduate * or graduate * or doctoral * or student * or professor * or instructor * or faculty or "preservice teacher * "or "pre-service teacher * ") 776,672 S14 TI (academic or "higher education" or universit * or college * or postsecondary or post-secondary) OR KW (academic or "higher education" or universit * or college * or postsecondary or post-secondary) OR AB (academic or "higher education" or universit * or college * or postsecondary or post-secondary) 471,711 S15 S8 OR S9 OR S10 OR S11 OR S12 OR S13 OR S14 1,033,468 S16 S7 AND S15 1,696 S17 S7 AND S15 Narrow 3.4. Source of Evidence Selection. Following the search, all identified records were exported and uploaded into Covidence (Covidence, Melbourne, Australia) and were then deduplicated using Covidence's deduplication function. We conducted pilot testing on a random sample of 25 titles/ abstracts and the team screened this sample using our predefined inclusion criteria. We discussed any discrepancies and clarified the inclusion and exclusion criteria to ensure consistency across the team. Once we achieved greater than 75% agreement across team members, all titles and abstracts were screened by two independent reviewers for assessment against the inclusion criteria. A third reviewer resolved conflicts in the title and abstract review. Literature studies that met the inclusion criteria were retrieved in full and assessed in detail by two independent reviewers against the inclusion criteria. Full-text studies that did not meet the inclusion criteria were excluded, and reasons for exclusion were provided. Disagreements that arose between two reviewers were resolved by a third reviewer.

Data Extraction.
We used a descriptive analytical method to extract contextual information from included literature. e review team developed a data extraction tool that we continually updated as new key findings emerged. We piloted the data extraction form on a random sample of 10 included articles to ensure consistency amongst the review team. Each included article was extracted by one team member using a standardized data extraction tool and was then verified by a second reviewer. Weekly meetings were held amongst team members to determine consistency in approach to data extraction. e data extracted included year, authors, publication title, journal, country, institutional affiliation, discipline, context/population, course description, course objectives, grand challenge topic, course assignments, study characteristics, and key findings in relation to the review questions. Any disagreements that arose between the reviewers were resolved through discussion and/ or a third reviewer.
3.6. Data Synthesis. Our synthesis included quantitative analysis using a simple numerical count and qualitative analysis using narrative synthesis in alignment with the objective of this scoping review. Article characteristics, grand challenge courses, and studies related to grand challenges in higher education were summarized in table formats. Narrative summaries were also conducted to add depth to the synthesis.

Results
After screening 8945 citations and 558 full-text papers, 55 papers met the inclusion criteria and were included in this scoping review (n � 55). e flow of data through our review is depicted in Figure 1. Table 2 displays the characteristics of the literature. e majority of literature came from the United States (n � 40, 72.7%) followed by the United Kingdom (n � 5, 9.1%). Prior to 2010, there were only 4 articles published on the use of grand challenges in higher education; however, the numbers have been climbing since, with 10 articles (18.2%) published in 2019 alone. e majority of literature focused on multidisciplinary teams of higher education students (n � 26, 47.3%), followed by engineering students alone (n � 18, 32.7%). Most of the grand challenge literature focused on undergraduate students (n � 36, 65.5%) followed by a mix of both undergraduate and graduate students (n � 10, 18.2%), then graduate students (n � 9, 16.4%). Almost every article included a description of a grand challenge course (n � 54, 98.1%), while only 25 articles (45.5%) included program evaluation or study data.
Multiple categories of grand challenges were addressed in the literature, the majority of which discussed sustainability issues and food and water insecurity. e topic of environmental sustainability encompassed a variety of challenges from sustainable agricultural practices to environmental health risks, such as soil erosion [20], creating sustainable energy required for developing affordable renewable energy sources, such as solar power [21]. For instance, Heinricher and colleagues [22] described a grand challenge that explored how to power up the world where the focus was on designing future energy-efficient homes and vehicles, such as green roofs and hydrogen cars. Other projects aimed at mitigating climate change through pollution sensors or carbon dioxide sequestration [23]. However, some of the major challenges in developing countries include food and water insecurity, and higher education students sought to combat these issues through the reduction of food waste and river cleaning robots [22,23]. In addition, world health grand challenges encompassed a wide variety of topics from advancing health informatics to engineering better medicines and improving resource allocation between hospitals [21,24]. Some developing countries struggled with mosquito-borne illnesses, such as malaria, and therefore, students were given the opportunity to develop solutions through the use of drones at California State University [25]. Other than preventing health risks, grand challenges also focused on improving urban infrastructure through sustainable cities and communities as well as strived to attain world peace through the prevention of nuclear terror and mitigating global violence [21]. Table 3 displays the summary of the grand challenge courses described in the literature. More than half of the courses (n � 28, 51.8%) included multidisciplinary (or interdisciplinary) learning as their primary course objective. Encouraging students to think and plan collaboratively, being part of an interdisciplinary team, along with the promotion of interdisciplinary knowledge, was recognized as a consistent objective in the courses. Many of the courses (n � 16, 29.6%) mentioned preparing students to develop innovative solutions to global problems while promoting the concept of sustainability as their major course objective [26,46]. Enhancing the problem-solving skills of the students with evidence-based learning concepts was recognized as another common course objective (n � 11, 16.6%) in the literature discussed. is included an improved ability to identify and understand the problem, work and plan around the available resources, and eventually develop viable solutions.
More than half of the articles (n � 28, 51.8%) mentioned some type of student professional development as a common course learning objective. Equipping the students with enhanced professional skills and promoting their career readiness was identified as a major aim. Improved communication skills [39], leadership [49], teamwork [67], and superior critical and strategic thinking abilities [22,43] were the common listed professional skills in the course objectives. Furthermore, refining the systems and entrepreneurial thinking of students [55] to make them more competent and competitive globally was listed as another common course objective. A few courses mentioned improved subject knowledge and modifications in the educational curriculum as their course learning objective [62]. Table 4 displays the summary of the grand challenge course assessments used in the grand challenge courses. e majority of courses included the use of design thinking projects (n � 48, 88.9%) and presentations (n � 26, 48.1%) as course assessments. Design thinking projects included problem-solving to propose creative solutions. Presentations took place within a course, at conferences, and as part of hackathons or competitions allowing students to demonstrate their knowledge to peers, students, instructors, and stakeholders. A few courses also mentioned the use of essays or reports (n � 13, 24%) and active discussions (n � 11, 20.3%) as course assessments. ese assessment tools promote the development of transferable professional skills among students including verbal and written communication, leadership, critical thinking, and adaptability. Table 5 displays an overview of the studies on the use of grand challenges in higher education classrooms. Students perceptions, opinions, and preferences in relation to grand challenge courses were most commonly explored (n � 12, 48%) [25,28,39,45,51,57,61,63,[66][67][68]72]. Eight studies (32%) aimed to assess students learning and knowledge development from participation in a grand challenge course [25,28,39,40,43,62,64,66]. Skills development was explored in six studies (24%) [35,44,59,61,63,67] while five studies (n � 20%) focused on evaluating the grand challenge courses themselves [20,24,30,38,67]. Only two studies (8%) focused on evaluating outputs of the grand challenge course and the impacts they may have on problem-solving attempts [31,36].
Of the 25 studies identified in this review, the majority (n � 10, 40%) were mixed-methods studies most commonly using surveys, focus groups, and interviews. Eight studies used qualitative methods only including focus groups, interviews, and reflective assignments (32%), and six used quantitative surveys (24%). One study included data on students' perceptions of a course without indicating how data were collected [45].   e authors reported on four main outcomes: (1) course satisfaction, (2) perceptions of the design thinking process, (3) perceptions of interdisciplinary group work, and (4) skill and knowledge development. In general, students were satisfied with grand challenge courses, course material, and course delivery [24,25,28,45,64,67,68]. e process of working on design thinking projects focused on broad ideas that could be tailored to individual interests aimed at proposing innovative solutions and providing relevant and valuable real-world learning experience for many students [20,28,30,31,36,40,44,45,51,59,61,62,[66][67][68]. However, some challenges to integrating design thinking projects were noted. Some students felt deficient in design thinking skills and wanted better preparation in design skills [30,39]. Other students struggled with ambiguous learning objectives, unclear structure, face pace, and lack of concrete solutions [20,24].

Education Research International
A number of authors reported on perceptions of interdisciplinary teamwork (n � 10, 40%). In general, students appreciated the interdisciplinary team collaboration [28,30]. One study reported that students with positive attitudes towards group work showed greater learning gains throughout the course [43]. In other studies, students noted that interdisciplinary learning helped prepare them for the real world of work and collaboration while offering valuable new perspectives, ideas, and knowledge to develop successful solutions to grand challenges [31,63]. In another study that reported on instructor perceptions, the teaching faculty found interdisciplinary team-teaching rewarding and felt that it enriched the class, amplified each other's teaching abilities, and supported professional skills development related to teaching and learning [30]. However, teamwork was not without its challenges. Gillet [38] noted that some teams were challenged with managing schedules or personal conflicts, while Gosselin and colleagues [39] reported that the multidisciplinary aspect created challenges in achieving course learning goals. e authors also reported on students' knowledge and skills development. Increased content knowledge was discussed in six studies [25,28,30,[66][67][68], while others discussed how students gained a more holistic and systemic understanding of grand challenge topics [35,57,63,67,68]. Although an increase in student self-confidence and competence was observed in three studies [44,61,67], students in another study noted, due to the interdisciplinary nature of the learning, they did not perceive they gained specialized knowledge in their main fields of study [57].
Although quality appraisal is not conducted as part of scoping review methodology [18,19], there are some important issues related to study quality that require further consideration. First, the diversity of methods, study designs, and reporting mechanisms made the identification of meaningful comparisons across the included studies difficult. Some studies did not include clear objectives and/or clear descriptions of data collection and analysis methods. e quantitative studies consisted only of cross-sectional descriptive surveys with the majority applying nonvalidated questionnaires that included very little methodological detail. e lack of description of the study details reduced our ability to generate an in-depth understanding of the impact of grand challenges in the higher education classroom. Overall, the generalizability of the studies included is limited.

Discussion
We undertook an extensive review of the grand challenge literature in higher education from inception to 2020. To the best of our knowledge, this is the first scoping review exploring the current state of the use of grand challenges as pedagogical innovations in higher education. A detailed review of 55 eligible articles revealed the contexts in which grand challenges are being used, common learning objectives and assignments used in grand challenge course work, outcomes related to the implementation of grand challenges in higher education classrooms, and gaps in the evidence to date. e results reveal a growing global interest in grand challenges in higher education while highlighting a lack of rigorous empirical evidence on the impact on student learning.               Design thinking project e most common grand challenge topics were focused on sustainability, climate change, and food and water insecurity. is may be due to the wide variety of topics related to environmental sustainability including agriculture, soil, and land use to reducing global environmental footprints, biofuel use, and ecological restoration. As well, sustainability topics have increasingly multifaceted characteristics, as they encompass a wide range of sectors in society from government policies and economics to public health and security [28]. A variety of disciplines are able to participate in grand challenges centered on sustainability as they incorporate diverse issues on preserving the environment and supporting development in a society.
Despite the variety of disciplines identified as engaging in grand challenge work, many disciplines remain underrepresented in grand challenge literature to date. For instance, healthcare disciplines were present in some of the multidisciplinary groups involved in grand challenges; however, there was a distinct lack of literature that focused on grand challenges specific to healthcare disciplines, such as nursing. Additional grand challenges that target real-world societal issues might benefit disciplines that work consistently in teams and high-stress environments, such as those in healthcare professions. Disciplines such as political science that are involved in government policies may benefit from the implementation of additional grand challenges in higher education curricula, to build critical collaboration and problem-solving skills required in developing and changing public policies. Furthermore, many potential grand challenge topics were not discussed in the literature. For example, the education discipline could target interventions on bullying or information; communication and technology disciplines could strive to ensure the safe use of artificial intelligence in common technology.
Incorporation of interdisciplinary learning was commonly discussed as a course learning objective and in the research findings. As suggested by Ivanitskaya et al. [73], interdisciplinary learning can create knowledge that is "more holistic than knowledge built in discipline-specific studies" (p. 97). By incorporating interdisciplinary perspectives into the learning process, students can acquire knowledge about various methodologies, theories, paradigms, and concepts from multiple disciplines and evaluate their thinking processes against perspectives offered by different disciplines [73]. Furthermore, opportunities to engage in interdisciplinary problem-solving can help students explore and develop solutions in a synthesized manner while also building personal and professional skills [74].
Klaassen [75] evaluated the nature of interdisciplinary learning and factors to be considered when integrating interdisciplinary opportunities into the curricula. e choice of problem, level of interaction between different disciplines, and constructive alignment were identified as important variables to be considered. Designing group assignments that require collaborative and multidisciplinary research and developing problems and questions that are identified in conjunction with key stakeholders were identified imperative in promoting interdisciplinary learning [76,77]. ese    Students Statistically significant difference in mean content knowledge scores between pretest and posttest (p � 0.000) Appreciated the team collaboration, research process, progress made, and support from the faculty and TAs 9 of 14 students strongly agreed they were satisfied with the course All students strongly agreed the classes stimulated to intellectual engagement with course material Faculty Strengths of the course were student participation, progress on proposing innovative solutions, and providing a rigorous and fun learning environment Most faculty were engaged with and satisfied with the course and plan to incorporate more problembased, student-centered learning into their courses Students A majority of students had positive responses to working in groups and working on the design thinking project e grand challenge topic was described as interesting, enlightening, broad enough to tailor it to your interests, and brought up a relevant and pressing contemporary issue that should be taught on a university-wide scale Students expressed an interest in having more knowledge about sustainability and better preparation in design skills Not surprisingly, the design students wanted more instruction in food systems while the liberal arts students felt deficient in design skills Faculty Students were engaged in class throughout the semester, acquired a solid understanding of sustainability and food systems issues, and quickly learned how to integrate visual design techniques into their projects Teaching as a team was rewarding and enriched the class, individual teaching abilities, and professional skills Dean (2017) [31] To explore the potential for authentic, interdisciplinary, collaborative learning to enhance educational and social outcomes for health, architecture, and landscape architecture students Qualitative study using focus groups for data collection and program/ project evaluation 15 nursing students, 10 architecture students, and 12 landscape students Students favoured authentic, " real-life" projects and learned about feelings and attitudes as well as knowledge e interdisciplinary learning prepares students for the real world of work and collaboration offered valuable new perspectives, ideas, and knowledge 26 Education Research International For some teams, the biggest challenge was that members dropped out part-way through, often due to scheduling conflicts or personal issues e most effective ingredients for building strong teams were students' own efforts to step up and become leaders  Students benefited from working in a ''real-world'' environment that required them to figure out what resources they needed to solve a problem Students expressed confidence in their ability to learn in the course Self-Efficacy test "I can figure out how to do difficult work" (p � 0.011) Self-Regulation test "I continue working even if there are better things to do" (p � 0.025), "I concentrate so that I will not miss important points" (p � 0.008), "I do not give up even when the work is difficult" (p � 0.009), and "I keep working until I finish what I am supposed to do" (p � 0.004) Johannes (1996) [45] To explore students perceptions of an interdisciplinary sustainable development course Authors did not indicate how they collected data

Interdisciplinary Engineering students
Students experienced the course as a useful addition to their engineering education e strong points of the course were freedom to define the problem, learning aspects of project-oriented work, teamwork, the multidisciplinary character (learning from other disciplines), and the contact with an external principal Project work was less effective for pure knowledge transfer Contact with students from other departments and the different disciplinary aspects were noted as a positive learning experience, while stimulating interdisciplinary thinking and study To explore students' perceptions of how problembased learning contributes to their understanding of sustainability competencies Qualitative case study Masters students in Law, Natural, and Social Science Students found problembased learning challenging but appreciated the opportunity to "do something different"; to "engage with law in a way that makes a difference"; to "consider a wide range of issues at once" and to have a tool they could use in their future careers which would enable them to consider a wide range of options Students consideration of cross-sectoral issues and legislative enforcement and effectiveness broadened their thinking about how different parts should interact and how this often fails to happen Petillion (2019) [72] To examine student feedback regarding the learning activities used in a course focused on addressing the United Nations Sustainability goals  Paired t-tests were completed at the start and completion of the course, with statistically significant increases in confidence for 10/15 statements on the survey related to design task confidence Focus group findings report that the style of learning used in the course was a factor involved with increasing selfconfidence Students also noted the importance of learning opportunities off-campus, increasing ability to contextualise needs All students agreed that being purpose-driven provided motivation for active engagement in the course   To assess motivation for applying to the program; evaluation of the course structure, logistics, and content To explore perspectives on and commitment to social justice To self-assess professional skills, active engagement, confidence, and growth in seeking leadership and academic opportunities Mixed methods: surveys and focus groups, pre-post tests

interdisciplinary undergraduate students
Survey results show that students felt highly engaged in the learning process Individual survey items indicated most or all students agreed or strongly agreed to items indicating a deep sense of engagement in selfdirected learning, and satisfaction with the structures supporting selfdirected learning 8 questions on engagement showed 100% of respondents agreed or strongly agreed, with the exception of "I received the support I needed to be successful in designing an actionable solution) in which 96.6% agreed/strongly agreed All the students reported that they were active participants, they increased their knowledge and understanding of topics that interested them, and they enjoyed the intensity of immersing themselves in learning and project development 100% of students agreed or strongly agreed that they see the world differently than they did before Students reflected that they see strengths in themselves that they did not previously see, and that they increased strengths they already had, becoming better versions of themselves. 100% of students agreed or strongly agreed with these statements Nearly 40% of students changed their study habits and two-thirds reflected a shift in how they participate in class as a result of this experience More than 60% of respondents changed their behavior in regard to seeking leadership opportunities and engaging in community service Nearly all current participants, and more than 85% of past participants, felt more integrated in their community may similarly be important considerations for those seeking to create multidisciplinary grand challenge courses. e promotion of critical thinking to develop a better understanding of societal problems was identified as a common learning objective in the grand challenge literature. As noted in our findings, critical thinking can facilitate thoughtful evaluation and strategic planning to develop innovative solutions to grand challenges. Walker [78] suggests questioning, classroom discussions, debates, and written assignments to be some of the best methods to promote critical thinking. Further, Hofreiter et al. [79] have suggested the use of real-world examples, such as societal grand challenges, as preeminent in promoting critical thinking skills. e most common course assessments were design thinking projects. Design thinking is a process that is analytic and creative which "engages individuals in opportunities to experiment, create and prototype models, gather feedback, and redesign" [80]; p. 330). Foshay and Kirkley [81] suggest the use of authentic problems, such as grand challenges, in conjunction with practice and assessments, as seen in design thinking assignments, to promote the development of problem-solving skills. Glen et al. [82] suggest that design thinking facilitates rapid learning, builds confidence in working with complex problems, and provides tools to develop diverse perspectives. In addition to helping build confidence, design thinking promotes the development of transferable professional skills including communication, integrative thinking, innovation, and collaboration [83].
Professional and personal skills development was identified as another common course objective and research finding. Singh and Gera [84] discussed the importance of skills development in higher education curricula and suggested the incorporation of collaborative pedagogy techniques and activities such as project work, practical learning, and group presentations to increase broader skill development. Nordstrom and Korpelainen [85] suggested creating videos, posters, and models, all of which are common to grand challenge courses, to help further enhance important professional and personal skills. Similar to design thinking projects, presentations, essays, and active discussions also promote the growth of transferable professional skills. Student presentations and active discussions help build the skills of verbal communication, active listening, networking, and time management, while written essays and reports promote the development of written communication, analytical skills, and professional language [84].

Gaps in Evidence and Suggestions for Future Research.
Research regarding the incorporation of grand challenges in higher education is still in its early stages. e impact of the design and delivery of grand challenge courses in higher Participants reported very high levels of satisfaction on their postcourse surveys A strong majority of participants (91%) agreed or strongly agreed that the course met their expectations, they gained something useful from the course, they enjoyed solving problems creatively, and they enjoyed working as an interdisciplinary team A majority (89%) agreed or strongly agreed that they enjoyed learning about homelessness Paired t-test showed that selfperceived knowledge increased (p < 0.01), change in attitude towards: society working collectively to address homelessness (p < 0.01), a contributing factor to people experiencing homelessness is failure of social systems (p < 0.01), participants should be involved in social system solutions (p < 0.01), and increased students reported participation in civic engagement (p < 0.001) education remains an underexplored area of research. To date, there are few comparative research designs and no experimental, quasiexperimental, or longitudinal research. Additional comparative studies are needed to identify effective approaches to design, embed, and promote the use of grand challenges as a pedagogical approach. Future research should also explore the involvement of females compared to males in grand challenges and how to promote equitable involvement of students in the minority.

Strengths and Limitations.
Although a robust and systematic method was used to identify all published literature on grand challenges in higher education, we cannot rule out the possibility that our search missed some relevant sources. Contacting grand challenge experts may have helped identify more grey literature to include in our review. A majority of the included studies were from the US. While this reflects the current state of evidence on grand challenge use in higher education, the disproportionate geographical representation may not accurately reflect grand challenge use in other higher education institutions from other countries.
e limited depth to which grand challenges have been empirically explored reduced our ability to make strong conclusive statements about grand challenge outcomes. Due to the heterogeneity of current grand challenge literature, no systematic review of grand challenge studies is possible at this time. In general, studies examining grand challenge use in higher education are weak in their methodological rigor and did not adequately explain their data analysis procedures, making it difficult to conclude that, based on these studies, grand challenge initiatives were successful in meeting their intended outcomes. Despite these limitations, the findings from this scoping review reflect the current state of evidence for the use of grand challenges in higher education while underscoring the need for additional research with robust study designs to better understand the impact and outcomes of grand challenge work.

Conclusion
is scoping review helped further our understanding of the use of grand challenges in higher education. While there are clear benefits to incorporating grand challenges into higher education curricula, future research is needed to determine how instructors and institutions can best incorporate grand challenge teaching and learning opportunities. In identifying what is known as well as gaps in the existing literature, this review helps further the development of, and ongoing improvements to, grand challenges in the context of higher education.

Data Availability
e data used to support the findings of this scoping review study are included within the article. Disclosure e corresponding author completed JBI Comprehensive Systematic Review Training at the Queens Collaboration for Healthcare Quality: a JBI Center of Excellence.

Conflicts of Interest
e authors have no conflicts of interest to declare.