Lectures have been the traditional T and L methodology across all disciplines in higher education (HE) (Brockliss, 1996). For centuries, the teacher-centered approach, in which students were passively receiving content, was never questioned (Skinner, 1976). T and L theories that make the student responsible for their learning, putting the student at the center of their own learning, have emerged. The initial fears associated with its inefficacy have been overcome by evidence-based research coming from different areas of knowledge (Freeman et al., 2014; Serin, 2018). These T and L theories are called active learning strategies and assume that students are highly engaged in their own learning. This factor is key to the success of active learning approaches.

The concept of academic student engagement refers to the active participation of students and their responsibility for their own learning. Examples of students being engaged include the effort that students invest in their learning process, the time spent in studying, the level of interest in the courses they are attending, and the implementation of good study habits (Markwell, 2007; Steele and Fullagar, 2009; Almarghani and Mijatovic, 2017) identified diverse factors to encourage students’ engagement, such as (i) the combination of active and interactive learning with co-curricular and extracurricular activities, (ii) the encouragement and support of academic and general staff to implement practices that foster student engagement, and (iii) the promotion of an inclusive environment.

Students perceived a positive change in their engagement consistently over time when experiencing active learning strategies (Kirstein and Kunz, 2015), even when students were in large classes (Hallinger and Lu, 2013).

Despite the inexistence of a universally agreed definition for active learning, there is consensus among the academic community on the general notion of students engaging in activities that push them to reflect on ideas and on how they are applying those ideas, such as talking, listening, writing, reading, and/or reflecting (Bonwell and Eisen, 1991; Hsieh, 2013; Misseyanni et al., 2018). Active learning approaches thus require students to systematically reflect on their level of comprehension and skills, when dealing with problems, challenges, or concepts in a certain course. The process of gathering information, thinking, and problem-solving keeps students engaged in participating and being mentally, and often physically, active in their own learning (Michael, 2006). Another consensual characteristic of the active learning approach is to be student-centered, where students influence the content, activities, materials, and pace of learning (Michael, 2006).

The literature presents a diversity of active learning approaches. Common student-centered active learning techniques are (i) cooperative learning (Dougherty et al., 1995), (ii) collaborative learning (Lumpe and Staver, 1995), (iii) problem-based learning (PBL) (Doig, 1993; Schmidt, 1994; Savin-Baden and Major, 2004; Spronken-Smith and Harland, 2009), (iv) discovery/inquiry-based learning (Wilke and Straits, 2001), (v) challenge-based learning (Roselli and Brophy, 2006), and (vi) concept mapping (Briscoe and LaMaster, 1991). Furthermore, flipped classroom (Saunders and Klemming, 2003; Pombo et al., 2017), TBL (Michaelsen et al., 2014), and peer instruction (Crouch and Mazur, 2001), among others, are also considered active learning approaches. According to Felder and Brent “Active learning is anything course-related that all students in a class session are called upon to do other than simply watching, listening and taking notes” (Felder et al., 2009).

There are many good examples of evidence-based research demonstrating the benefits for all the players involved in using active instead of traditional learning methodologies in pedagogical practices (Michael, 2006). Indeed, it has become clear that class attendance and engagement are higher, and students learn more. Recently, Freeman and colleagues meta-analyzed 225 studies and concluded, by comparing tests grades from undergraduate students under traditional versus active learning, that the average tests grades improved by approximately 6% in active learning, and students under traditional learning were 1.5 times more likely to fail than students under active learning (Freeman et al., 2014).

However, the perception of learning in active learning classrooms is lower than that in passive environments. This fact was shown by comparing self-reported perceptions of learning with real learning. The authors suggested that initial cognitive effort applied in active learning may be detrimental to the learning motivation of students. This is usually overcome with time, when students realize the benefits of their own engagement in the learning process (Barr and Tagg, 1995; Deslauriers et al., 2019).

Still, there are also critical issues when implementing active learning strategies: (1) the learning environment must be built by the professor who needs to be familiar with active T and L approaches, thus, faculty development is key; (2) the ratio professor/student is usually higher in active learning than in traditional teaching, which increases the number of professors that need to be hired; (3) suitable infrastructure is needed (appropriate classrooms for group work, for example); (4) supporting infrastructure for research and teaching, and (5) learning designers (Børte et al., 2020).

The following paragraphs detail the active T and L methodology implemented in the context of this study: a combination of TBL and SL methodologies.

TBL is a student-centered and teacher-directed strategy that includes in-class teamwork and assessment, promoting the benefits of small-group teaching in a large-group setting (Parmelee et al., 2012). This methodology has been shown to improve student’s grades and classroom engagement (Clark et al., 2008; Chung et al., 2009; Parmelee, 2010). Further, the professors reported increased excitement in their classrooms (Dana, 2007; Nicoll-Senft, 2009; Andersen et al., 2011; Jacobson, 2012).

The perception of students is that TBL is interesting, allows for a deeper understanding of content, and prepares them more efficiently for assessment (Swanson et al., 2019). Indeed, TBL students outperform non-TBL students in examinations (Koles et al., 2005, 2010; Letassy et al., 2008; Zingone et al., 2010; Grady, 2011; Thomas and Bowen, 2011; Persky, 2012; Fatmi et al., 2013). Furthermore, it has been shown from the analysis of 20 years of results that 99.95% of teams outperformed their best member by an average of 14% (Michaelsen, 2002).

In TBL, the formation of groups is key to the success of the method. The professor should create the teams based on students’ skills diversity and other relevant characteristics, and the groups should be kept as long as possible (Parmelee et al., 2012). TBL is characterized by three key components: (1) a pre-class content preparation phase; (2) an individual test followed by the same test, performed in groups, after which, the teacher makes a clarification review; and (3) a content application activity, usually a significant problem, which they must interpret and, as a team, organize an answer and be able to explain and defend it (Figure 1A; Kibble et al., 2016; Chhabra et al., 2017; Reimschisel et al., 2017). In general, four principles govern the methodology: (1) groups must be properly formed and monitored; (2) students must be held responsible for their individual and group work; (3) group tasks should promote group learning and development; (4) the professor must give frequent and immediate feedback (Michaelsen et al., 2007).

Unlike in other group work-based methods, in TBL a single professor can facilitate/follow the work of several small groups (5–7 students) within a classroom with many students. It should be noted that TBL was introduced by Michaelsen in the 1970s when he went from a class with 40 to 120 students (Michaelsen et al., 2007). Interestingly, students perceived a larger class size as beneficial to their learning with TBL (Michaelsen, 2002).

SL is a T and L methodology that allows information to be quickly captured in long-term memory, based on a particular classroom organization (Figure 1B). It relies on the ubiquitous phenomenon in learning and memory, the spacing effect, first shown by Ebbinghaus (Fields, 2005; Ebbinghaus, 2013). The spacing effect is characterized by the observation that long-term retention is improved if a longer interval exists between study repetitions (Melton, 1970; Kelley and Whatson, 2013; Garzia et al., 2016; Kim et al., 2020).

A common SL class comprises 3 moments (~20 min each) with intense input of information–stimulus–separated by two intervals (10 min–distractors) that must not be related to the content of the class (Kelley and Whatson, 2013). In the first input session, the information that students need to learn is provided and they start to build new memories of the new content they are learning. An interval follows which should not stimulate the same memory neural pathways, thus different activities must be done (preferably manual or physical activities). The second information input session serves the purpose of recalling and revising the key contents of the first, allowing for memory arousing. This may include presenting the content using alternative strategies, for example, short videos or filling blank spaces (in the slides presented in the first session). This session is followed by a second interval that respects the same principles. In the third input moment, student-centered activities are used, so that they can demonstrate the acquisition and comprehension of the contents from the first two sessions (Garzia et al., 2016).

A recent review of SL applied to the education of health professionals (Versteeg et al., 2020) concluded that there is a void in the definition of SL in the health profession education literature. The authors identified the need to invest time and resources in helping learners from the health profession retain the information being learned (D’Eon, 2006) through SL approaches.

Furthermore, the application of SL in combination with other methodologies, for example, Inquiry-based learning, has been suggested (Kelley and Whatson, 2013).

The academic year 2019/2020 was the first year of a profound curricular transition in the Biomedical Sciences Degree in the Department of Medical Sciences at the University of Aveiro. It is important to take into consideration that the students were already familiarized with active learning methodologies, e.g., PBL, in one course per semester. Thus, they were open-minded regarding innovative teaching and learning strategies. This fact facilitates the implementation of new and different teaching and learning experiments.

Seizing this opportunity for change, the professor responsible for the course on Integrative Biochemistry decided to follow the trend that was being implemented, not only in medical but also non-medical schools, and move from traditional lectures, a strategy usually developed in theoretical biochemistry classes, to an active T and L strategy, combining TBL (Kibble et al., 2016; Chhabra et al., 2017) and SL (Kelley and Whatson, 2013; Garzia et al., 2016; Figure 2). The implementation of this T and L strategy was also driven by the growing amount of information available online, which leaves more room for knowledge application activities.

An interdisciplinary group of colleagues (professors, researchers, and non-teaching staff) from the university was involved in this project to help change the conventional way of thinking, both for students and professors. Thus, the main goal of the innovative T and L approach was to promote student engagement while learning occurred in a three-hour class with a theoretical matrix by achieving the following specific objectives: (1) to implement active learning strategies: combining SL and TBL; (2) to develop collaborative and interdisciplinary practices among a group of colleagues with different skills and visions toward T and L; (3) to include students as partners in the design of the T and L environment; (4) to collect and analyze evidence regarding pedagogical practices that can regulate T and L during the academic year; (5) to share the results with the academic community and foster knowledge transfer to similar pedagogical contexts.

A typical class includes several well-defined moments (Figure 3) which are detailed in Table 1. The class structure can be used at distance or face-to-face.

The assessment was discussed with the students and included an individual and a group component. The main assessment elements (Table 2) were written exams, peer evaluation, TBL evaluation, a project, and attendance.

The tests (Element A in Table 2) included multiple choice questions, False/True questions where the false should be changed to become true, and questions to analyze clinical cases or apply knowledge in new contexts. In terms of Bloom’s level, the tests included remembering, understanding, analyzing, and applying.

Concerning Element E (Table 2), students had in total ~ 10 classes with the TBL methodology (the others were tests). Of those 10, only 3 (for each student) were taken into consideration for their assessment. The other classes were used for formative assessment.

The students developed a project (Element F, Table 2) on metabolic maps in which the output was a poster that was presented at the end of the semester to the class.

This study aimed to understand the impact of implementing a pedagogical innovation in a large class of 1^st year students which included the combination of TBL and SL strategies and analyzing the impact on students’ engagement.

The implementation of this pedagogical innovation occurred in two phases: (1) a Pilot Study and (2) Full Project. The pilot study was conducted in the second semester of the 2019/2020 academic year in the Integrative Biochemistry course. The pilot study was reported by quantitative data (closed questions of a questionnaire; Supplementary Table S2) and qualitative data (open-ended questions of the same questionnaire, Supplementary Table S2). Initially, 14 classes were supposed to be attended by the students. However, the COVID-19 pandemic forced all of us to go to distance learning, and the original planning for the course was altered. Only four classes were based on TBL and SL. Thus, the questionnaire was answered by the students at the end of the semester taking into consideration the experience of the four classes that occurred before the lockdown. The full project was implemented in the second semester of the 2020/2021 academic year in the same course. To monitor the full project implementation, the methodology of design-based research was implemented (Wang and Hannafin, 2005; Amiel and Reeves, 2008). The monitoring data collection was carried out before (before action), during (during action), and after (post-action) the project (Table 3) and included different instruments: a final questionnaire (Supplementary Table S3), a focus group, the professor diary, and teachers observation. Furthermore, some of the Quality Management System (SGQ) indicators from the university were also analyzed, including aspects related to teacher performance and course characterization (Supplementary Table S4).

This study focuses on the first-year students of the undergraduate degree of Biomedical Sciences at the University of Aveiro enrolled in the curricular unit of Integrative Biochemistry in the academic year 2019/2020 (n = 170, pilot study) and 2020/2021 (n = 147, full project).

In both implementation phases, satisfaction questionnaires were used to obtain quantitative data. The final questionnaires included both quantitative and qualitative data (Supplementary Tables S3, S4). The remaining instruments collected qualitative data.

A focus group was established consisting of 5 students in the full project phase. The focus group participated actively in the project implementation. This group was convened at the beginning of the semester (18/02/2021) and at the end (14/04/2021). The focus group interviews were recorded and transcribed afterward. Furthermore, the focus group gave regular feedback by email after each class. In all the feedback moments the focus group students were asked to identify positive and negative aspects and suggestions.

The teacher maintained a diary aimed at registering the comments on her practices, including suggestions for future changes.

Additionally, systematic observation by teacher colleagues from the university who gave written feedback was also registered for future analysis.

Qualitative data obtained in the full project including focus group feedback, teacher diary, systematic observation, and open feedback comments from students was subjected to content analysis through the following steps: (1) pre-analysis to understand the documents’ structure and organization, which consisted of a floating reading of their content; (2) text selection operations to code the excerpts according to the predefined categories; (3) more detailed exploration of all the data, in which text was divided into units of meaning and a code was assigned to each of these units (Kuckartz, 2019; Gläser-Zikuda et al., 2020). The analysis was performed using WebQDA software¹ and a tree analysis category system was designed and implemented. Three categories were selected for content analysis: A. Strengths; B. Weaknesses; C. Suggestions.

Descriptors for content analysis were: 1. Type of Participant: 1.1 Teacher in charge; 1.2 Students; 1.3 teaching colleagues; 2. Research stage: 2.1 Before action; 2.2 During action; 2.3 Post-action (Table 4). To complete the qualitative data analysis, two researchers read the documents and selected relevant passages, coding them in the categories A, B, or C, according to the descriptors described above. Validation of the categorization process was performed by two members of the team, allowing for the standardization of the criteria used for the analysis. Once this stage was completed, the results were systematized. Frequency counts of the relevant categories and descriptors were obtained. This provided a crude overall picture of the material being analyzed. Finally, the researchers proceeded with the interpretation of content, selecting excerpts that translated the different categories.

The quantitative data in the questionnaire response was subjected to statistical analysis performed using IBM Statistical Package for Social Sciences (SPSS), version 21.0 (IBM Corp., Armonk, NY, United States). Variables normally or not normally distributed were reported as mean and standard deviation, and median (interquartile range - 50), respectively.

At the end of the semester, the students filled out a structured questionnaire, classifying the T and L experience. To generate a comprehensive picture of the students’ perspectives, the survey combined a quantitative and qualitative approach. Each topic that was quantitatively assessed by the student included several questions related to that issue, rated on a Likert scale (1–7). Answers of “1” indicated the most negative response (completely dissatisfied), while “7” was the most positive (completely satisfied). The questionnaire from the full project included more questions than the one from the pilot. The alteration was based on the analysis of the results from the pilot study. Students were also asked to identify positive and negative aspects of their T and L experience. The qualitative part of the questionnaire will be analyzed in the section below. To assure the anonymity of students, no personal data were collected.

In the pilot study, of the 170 students, 106 answered the questionnaire (Table 5A).

From the results, it can be concluded that most students stated they were learning better with TBL + SL than with traditional classes (4,59 ± 1,86) and also that they enjoyed the activities of the SL breaks. Nevertheless, there is space for improvement since ~25% of the students considered that they did not learn better with TBL + SL than with traditional theoretical classes (they rated the question “I learn better with TBL and SL than with traditional theoretical classes” 1, 2, or 3). Also, 19 students of the 106 responders considered that the physical/manual activities in the middle of the classes were not important (they rated the question “How important were for you the physical/manual activities in the middle of the classes” 1, 2, or 3). This suggests that four classes using the implemented approach (TBL + SL) were perhaps not enough for the students to appreciate the full potential of the new pedagogical method.

Concerning the full project, from the 147 students, 45 answered the questionnaire (Table 5B). The low number of responses can be explained by the fact that the questionnaires were sent to the students to be filled out online and their fulfillment was not compulsory. In the pilot project, the questionnaires were given to the student on the day of the last exam, and they were asked to give them back at the same time they gave the exam sheet. The results from the full project suggest that the students appreciated the course as a whole. The perceptions of the students in the full project seemed to be even more satisfied than the perceptions of the students from the pilot study. This fact suggests that the slight alterations made after analyzing the negative points and suggestions of the students from the pilot study were crucial. Comparing the global question, the satisfaction increased from 4,59 ± 1,86 to 5,44 ± 1,45.

Regarding the impact of TBL, students expressed that the individual questionnaire (IQ) at the beginning of the classes was crucial to test their autonomous study (5,91 ± 1,35) and that the group questionnaire (GQ) was relevant to improve their knowledge based on peer discussion (5,89 ± 1,29). The students realized that the SL physical activity was important (5,98 ± 1,60). The existence of several assessment components did not please everyone (4,87 ± 1,51) as this was the question with the lowest evaluation. The students considered that peer evaluation was relevant for the group dynamics (5,80 ± 1,34). Additionally, the students stated that TBL random evaluation made them study throughout the semester (5,84 ± 1,09).

At our university, there is a Quality Management System (SGQ) of the T and L process that aims to improve teachers’ practices by surveying the students about different aspects of their courses. This system allows us to attribute a Good Pedagogical Practice stamp to the courses which have an overall answer higher than 8 (on a scale of 1–9). In the Integrative Biochemistry course that is being addressed here, this stamp was attributed.

The SGQ questionnaire includes several questions that should be answered by all students, although this was not compulsory, which explains the n = 50. Here we highlighted the most relevant questions for the article and its discussion (Table 6).

Students felt that the course was organized (7,40 ± 1,75), the recommended bibliography was adequate (7,90 ± 1,48), and the assessment was fair (7,43 ± 1,81). Overall, they agreed that the course functioned well (7,51 ± 1,40). At the same time, the students stated that they required a huge amount of time working on this course to obtain final approval (8,27 ± 0,96). This aspect highlights the lack of students’ knowledge of how much time should be dedicated to a discipline based on the European Credit Transfer and Accumulation System (ECTS) credits it is worth, which for the course in question, is 6 ECTS credits. Thus, 6 ECTS credits correspond to a total load of 162 h of dedication during the semester. The answers obtained from this question will allow for improvement in the following academic year by explaining in the first class how many hours they should dedicate.

The students perceived that their teacher performed well (8,16 ± 0,94) with the ability to stimulate and motivate students (8,02 ± 1,20) and they created a favorable climate for learning and active participation of students (8,33 ± 0,93). Furthermore, the teacher encouraged their autonomy (8,53 ± 0,54), while also monitoring their work (7,98 ± 1,34).

Pilot study data qualitative analysis allowed the identification of relevant aspects of the pilot project implementation. From the students’ feedback analysis, improvements were possible in the full project implementation. In total, students had 63 positive highlights and 13 negative aspects (Supplementary Table S5). Overall, students stated that the positive aspects of the pilot study included the SL physical activities, the good and secure environment of the classes promoted by the teacher, and the pedagogical innovation implemented.

In contrast, the negative aspects concentrate on the problems associated with group work.

This is a common problem in every working group, not only at the university level but also professionally (Isaac and Tormey, 2015). Group work is usually not an immediately rewarding experience for students (Colbeck et al., 2015). Some students have to deal with questions of leadership, conflicts, and the egos of group members, which can become very stressful issues for students (Ford and Morice, 2003). Faculty guidance is key to dealing with group issues. Nevertheless, it is crucial to make students realize the relevance of group work to their future as professionals.

Student’s feedback allowed the identification of the following aspects to be improved: (1) the need to prepare more concise content/ bibliography for pre-class study; (2) the need to optimize the time spent on IQ and GQ; (3) the need to change the evaluation mode (inclusion of 2 tests in the semester); (4) the need to listen to students’ opinion in the development/preparation of the course. All these aspects were taken into consideration and incorporated into the full project implementation.

Qualitative data analysis of the full project included not only the student feedback but also the opinion of the teacher and teaching colleagues. Furthermore, a deeper analysis of the content was performed in comparison to the simple analysis of the pilot study. All data from the full project used to perform the content analysis is presented in Supplementary Table S6.

An overview of the results (Table 7) allows us to conclude that from a total of 428 comments that were annotated, 53% were strengths, 26% were weaknesses, and 21% were suggestions. The students were the participants that contributed the most comments, 315 in contrast with 97 from the teacher and 16 from the teaching colleagues. Interestingly, the teaching colleagues only commented on the strength category.