Promoting High-Order Thinking Skills through Problem-Based Learning: Design and Implementation

PBL (Problem-Based Learning) has significant importance in enhancing critical thinking, creative thinking, problem-solving, and promoting HOTS (Higher-Order Thinking Skills) and 21st-century skills. However, while there has been a lot of research on PBL, most of it has focused on the fields of medicine and physics, with few and often disorganized studies in the field of education, especially those using literature review methods. The purposes of this study are: (1) to classify and compare case studies on "Problem-Based Learning" and extract relevant conclusions, and (2) to summarize universally applicable "PBL" teaching strategies and provide recommendations. This review focuses on the specific implementation procedures of PBL teaching strategies over the past decade. The study finds that in teaching contexts such as group collaborative learning, role-playing, and STEAM (Science, Technology, Engineering, Arts, and Mathematics), problem-based teaching can effectively promote the development of students' critical thinking, creativity, problem-solving abilities, and other higher-order thinking skills. This research enriches the theoretical foundation of PBL operational procedures and provides important references for teaching practice.


Introduction
The importance of PBL teaching strategies for HOTS and 21st-century skills has prompted researchers to explore PBL teaching strategies.There have been two previous definitions of PBL.The first definition considers it a learner-centered teaching method, where learners can conduct research, integrate theory and practice, and apply knowledge and skills to develop feasible solutions for predetermined problems (Savery, 2015).They believe that higher-order thinking skills are cognitive skills based on analysis, evaluation, and synthesis as outlined in Bloom's Taxonomy.Critical thinking and logical thinking fall under "analysis," creative thinking and reflective thinking fall under "synthesis," and problem-solving skills and decision-making Despite the introduction of PBL in the 1960s, school teachers lack understanding of HOTS, and most currently teach using LOTS.Relevant research is primarily concentrated in the medical field, with few studies in the field of education.In particular, studies employing literature review methods are scarce and the research conclusions are often inconsistent (Anggraeni et al., 2020;Rustam et al., 2022;Polyzois et al., 2010).The implementation of PBL (Problem-Based Learning) in education also faces numerous challenges and various complex obstacles (Tefera et al., 2024).For instance, decreased student engagement, poor support for the practice of critical self-reflection, and issues that hinder group functionality can negatively impact both the implementation process and the outcomes of PBL (Khoiriyah et al., 2015;Li et al., 2023).Some researchers believe that PBL, as a higher-order thinking teaching method, is becoming increasingly important in teaching practice due to the limitations of subjectbased, teacher-centered curricula in education (Frost, 1996).However, other researchers hold a different view, arguing that the evidence for the effectiveness of PBL over traditional teaching methods is still inconclusive (Kulo & Cestone, 2023).Therefore, even though PBL holds significant importance, its role in education needs to be viewed dialectically.The relatively scarce research on PBL, the numerous debates surrounding it, and the many implementation obstacles have driven researchers to actively explore PBL and HOTS.This review focuses on comparative research, examining and comparing specific implementation methods of the PBL teaching strategy in previous case studies.It aims to extract relevant conclusions, summarize the advantages and disadvantages, and strive to derive a universally applicable teaching model.

Search Parameters
Systematic Literature Review (SLR) is a well-known research method (Thomé et al., 2016).The literature sources for this study include electronic databases such as Google Scholar, Web of Science, Mendeley, CNKI, etc., encompassing academic journals, conference papers, books, etc.The key thematic terms are "PBL," "HOTS," and "21st-century skills," and the retrieval period spans from 2014 to 2024.

Selection Process
Two researchers from the education field were responsible for the literature selection and verification for this review, while one researcher from the computer field was responsible for data processing and coding (Hu Xiaoling et al., 2024).In the first stage of literature screening, using the keywords "problem-based learning" AND "High order thinking," 592 open-access articles were retrieved.In the second stage, 21 articles not belonging to the period of 2014-2024 were excluded, leaving 571 articles.In the third stage, after preliminary screening of titles and abstracts, 417 irrelevant articles were removed, leaving 150 articles.In the fourth stage, after reading the full texts, 128 articles were further excluded.Finally, 22 articles were selected for this study.Duplicate citations were removed using the Zotero software.
To ensure the quality of the review, strict inclusion and exclusion criteria were applied throughout the literature selection process.Here is a summary of the inclusion and exclusion criteria for literature selection: 1. Inclusion Criteria: (1) Published between 2014 and 2024.

Exclusion Criteria
(1) Articles not published between 2014 and 2024.
(2) PBL is not the main variable under study among several independent variables.
(5) Literature is not open-access, and full-text is not available.Table 1 of the PRISMA flowchart illustrates the literature selection process of this study (Zakaria et al., 2019;Haddaway et al., 2022).

Table 1 PRISMA Flow Diagram
The researcher analyzed the distribution of literature used for this study after strict screening.Table 2 shows the distribution of literature.From Table 2, it can be observed that studies related to Problem-Based Learning are mainly concentrated in the field of natural sciences, with the most studies conducted in the field of mathematics, and there are few literature studies related to PBL in the social sciences.In terms of research methods, most PBL studies are quantitative.Therefore, it is concluded that there are relatively few related studies on PBL in social science fields such as education and psychology, especially qualitative studies.In this study, the researcher adopted a qualitative research strategy and conducted a literature review to investigate the specific implementation of PBL teaching strategies in case-based teaching.The researcher categorized this study into three types using content analysis: (1) Significant Impact* Table 3 summarizes the implementation methods and steps of Problem-Based Learning teaching strategies in quantitative research.From the results, it is evident that the implementation methods of PBL in quantitative research are mostly experimental studies, with specific steps as follows: (1) Sample selection: Independent and dependent variables are the experimental and control groups, respectively; (2) Testing steps: posing questions, pretesting, application of PBL, post-testing; (3) Result analysis: descriptive or inferential analysis of the test results.Inferential analysis mainly includes calculations of Kolmogorov-Smirnov normal distribution, homogeneity test, ANOVA, and t-test.From the results in Table 3, it can be concluded that the implementation of PBL measured in quantitative studies has a positive impact on the development of higher-order thinking skills.Literature search, criteria formulation, and implementation of literature selection; (3) Literature summarization and coding; (4) Result analysis and reporting.The research conclusions extracted from all the literature reviewed unanimously acknowledge the mutual influence between PBL and HOTS.

Implementation of PBL Teaching Strategies in Mixed Research
Significant Impact* From Table 5, it can be observed that the application of PBL in mixed research has a promoting effect on higher-order thinking skills.Mixed research based on problem-based learning combines quantitative and qualitative research methods, with quantitative research conducted first followed by qualitative research analysis.This requires us to integrate the implementation strategies of both quantitative and qualitative research mentioned above and conduct more systematic and complex analysis of the data.

Results
Through the selection, summarization, and analysis of literature, we have come to understand that there is still a gap in research on PBL in the field of education, with PBL research mainly

Discussion
This study summarizes qualitative, quantitative, and mixed-method research on the implementation of PBL teaching and uses the PRISMA flowchart for literature quality assessment.Mixed-method research designs integrate quantitative and qualitative data, producing better results than using a single method alone (Minc et al., 2022).This enhances the credibility and validity of the research findings.This study refutes the views that PBL teaching has negative impacts or that its effectiveness is inconclusive (Sains, 2022;Kulo & Cestone, 2023).This aligns with the consensus of the majority of researchers (Darmayanti et al., 2021;Wahyuningtyas et al., 2023;Syahputra & Surya, 2014).This study, by summarizing and analyzing previous research, avoids duplication, identifies research gaps, and summarizes general teaching strategies.It enriches and extends the existing theories of PBL teaching strategies and develops new theories for the implementation of PBL teaching.The universally applicable PBL teaching implementation model proposed in this study can be used as a tool for curriculum design, implementation, and collaborative innovation, providing important references for educational practice (Shimizu et al., 2021).Specifically, the implementation of PBL teaching strategies is guided by teaching models such as role-playing, STEAM education, group collaboration, and inductive-deductive methods.
Teaching through PBL helps deepen students' understanding and retention of knowledge, and promotes problem-solving.It also aids in developing students' teamwork skills and autonomous learning abilities, enhancing higher-order thinking skills such as critical thinking, creativity, and problem-solving abilities.Additionally, it supports the development of educational practice (Prastiti, 2020;Syahputra & Surya, 2014;Wildan et al., 2021).However, PBL teaching strategies also face some challenges.They can potentially lead to time wastage, some students may develop negative emotions, and the assessment of PBL teaching is fraught with uncertainties.However, PBL teaching strategies also face challenges, including the potential for time wastage, the possibility of negative emotions among some students, and uncertainties in PBL teaching evaluation.This study has limitations as it involves analyzing and commenting on previous research results, and the selection of literature and conclusions may be subjective and should be treated with caution.Future research suggestions:(1)Apply the general teaching strategies identified in this study to specific PBL teaching practices and evaluate their universal applicability.
(2)Focus more on evaluating PBL teaching strategies and innovating a universally applicable teaching model.
(3)Pay more attention to the impact of teaching strategies on Higher Order Thinking Skills.(4)Developrelevant technologies for PBL teaching to make it more systematic and scientific.

Implementation of PBL Teaching Strategies in Quantitative ResearchTable 3
Implementation of PBL Teaching Strategies in Quantitative Research

Table 4
Implementation of PBL Teaching Strategies in Qualitative Research

Table 4
analyzed the implementation strategies of PBL in qualitative research, and the results showed that the common implementation strategies of PBL are in the form of interviews or literature reviews.The implementation steps of PBL interviews are as follows: (1) Research design: constructing research questions, determining samples, preparing observation forms and interview guides; (2) Classroom observation and recording, post-class interviews and recording; (3) Reviewing, analyzing, evaluating, and reapplying the results.The implementation steps of PBL literature review are: (1) Constructing research questions; (2)

Table 5
Implementation of PBL Teaching Strategies in Mixed Research in the natural sciences.Consistently across qualitative, quantitative, and mixed research, it has been found that PBL has a positive impact on higher-order thinking skills and 21st-century skills.Therefore, we can actively explore PBL teaching strategies in teaching practice.In this study, researchers summarized the PBL teaching strategies in qualitative, quantitative, and mixed research as follows: concentrated