In the era of rapid technology development, one of the main goals of education is to foster fast and meaningful learners and creative problem-solvers who are not only able to adapt well in the rapidly changing environment but also make this environment progress further (Ayyildiza & Tarhanb, 2018; Chan, Hue, Chou, & Tzeng, 2001; Kirschner & Merriënboer, 2013; Prince, 2004).
In the context of higher education, lectures continue to be the most dominant method of transmitting information and there has been a growing acceptance of learning theories that emphasize the process of actively constructing knowledge (Arthurs & Kreager, 2017; Bransford, Brown, & Cocking, 1999). In contrast to lectures, which frequently set up students for passive learning by focusing on memorizing facts and information (Harlen & James, 1997), the introduction of the active learning approaches was shown to be more effective than lectures alone at developing students’ general cognitive (Halpern, 1999) and social (Bosworth, 1994) skills.
Active learning can be defined as a set of approaches to a curriculum that engage and challenge students in the learning process through a range of activities, often collaborative and reflective, both inside and outside the classroom (Freeman et al., 2014; Zepke & Leach, 2010). Active learning is a hallmark of Curriculum 2021, an initiative from the University of Liverpool (Centre for Innovation in Education, University of Liverpool, n.d.). The results from several studies in chemistry education indicate that students experience greater academic success upon engagement in active learning processes where they discuss and comment on the subject, role-play scientific scenario, emulate the industrial and academic research environment compared to when they are engaged in passive listening to the teacher (Ayyildiza & Tarhanb, 2018). Active learners regularly review their learning process in situ and identify what they need to learn next either by themselves or with the help of a tutor (Darling-Hammond, Flook, Cook-Harvey, Barron, & Osher, 2019). Application of in-class and out-class active learning strategies, in particular, when concerning cooperative and group work, may have a greater potential to model real industrial and academic research environments, thereby being helpful for future employment (Barkley, Cross, & Major, 2005; McLinden, Edwards, Garfield, & Moron-Garcia, 2015).
Enquiry-based learning is a form of active learning that emphasizes students’ questions, ideas and analyses (Dostál, 2015). From a student perspective, inquiry-based learning focuses on finding a solution to a question or problem using evidence-based reasoning and creative problem-solving. From a lecturer perspective, inquiry-based teaching induces an active approach to student learning by stimulating critical thinking and a deeper understanding of the topic. Presentation of results and their discussion at the final stage of this exercise creates conditions for a deeper interaction between teaching staff and students and an opportunity for more personalized feedback on activities (Bell, Urhahne, Schanze, & Ploetzner, 2010).
Two of the most attractive inquiry-based strategies include problem- and case-based learning and teaching. There are many definitions of these approaches in the literature, and for the purpose of this study we would like to adapt the following ones. Both problem-based learning and case-based teaching are student-centred instructional strategies in which students learn about a subject through the experience of analytical thinking on an open-ended problem, attempting to find a meaningful solution (problem-based learning) or reflecting on a solution already proposed (case-based teaching) (Rhem, 1998; Walters, 1999). Both approaches allow students to define their learning objectives based on the cues in the scenarios and challenge students to use an array of problem-solving techniques and self-directed learning strategies. While in problem-based learning students are primarily focused on constructing their way towards a unique solution of a problem given, in case-based teaching an impact is shifted towards developing skills in reflective judgement by reading and discussing a complex real-life scenario that might, at least partially, be solved (Crosling & Webb, 2002; Herreid, 2007).
In recent years, fast development of analytical instrumentation has prompted dramatic changes in teaching analytical chemistry at university level. Whereas the instruction of core analytical chemistry subjects continues to be of high significance, implementation of additional applied analytical approaches helps to bridge the gap between more theoretical ways, characteristic of academic teaching, and more practical ways typical of post-study employment. Although the use of problem- and case-based learning scenarios in chemistry have shown to be beneficial, evidence of their applications for teaching of analytical chemistry, and in particular its instrumental or applied components is limited to but a few examples (Fitri, 2017; Gao, Wang, Jiang, & Fu, 2018; Larive, 2004; Yoon, Woo, Treagust, & Chandrasegaran, 2014). Larive has stated that although problem-based learning methods can be applied in the classroom as a supplement to or in lieu of traditional lectures (Wenzel, 1999, 2000), the analytical chemistry teaching laboratory is an ideal environment to utilize problem-based learning. The author linked the efficiency in application of problem-based methods in teaching to the quality of problems given to students (Larive, 2004). Fitri has concluded that the application of problem-based learning for teaching quantitative analytical chemistry improves the students’ knowledge, skills, ability, and attitude (Fitri, 2017). In addition to subject learning, students have acquired both experience and practical skills in analysis of industrially derived essential oils; this experience and these skills can be transferred to yield solutions to quantitative analytical chemistry problems derived from other fields.
In practice, we have recognized that the major concern in a wider application of problem- and case-based methods in teaching instrumental analytical chemistry is the lack of suitable models for trialling these approaches before implementation. Owing to the complexity and extent of the modern chemistry curriculum and its clear inclination towards more applied components (i.e. employability), a trialling element turns a cornerstone for successful implementation of new teaching initiatives (Brew, 2003). In this report, we introduce and discuss a two-step model for trialling problem- and case-based scenarios for the instruction of applied analytical chemistry that was helpful for the development of several chemistry modules for both undergraduate and postgraduate provision at the University of Liverpool. We start by introducing the main research question, followed by the discussion of the approach proposed, and identification of the benefits and limitations.
This study introduces the two-stage model for trialling problem- and case-based learning teaching scenarios in chemistry education. The main research question we try to answer is: does this two-stage approach have benefits over conventional ex-situ trialling models? To answer this, we attempt to understand whether this model is more representative and reliable allowing the results to be directly transferred to the curriculum design. Positivist paradigm is used as a conceptual framework for this study as it is primarily based on empirical hypothesis testing, and its findings are expected to be extrapolated to other studies of a similar type.
Following the extensive feasibility studies (without collecting personal data), the analysis of students’ feedback, observation of their activity and levels of engagement as well as their interview were used further as the primary source of information. Students’ opinions on the impact of the introduction of elements of problem- and case-based teaching on the process of student learning were also analysed to stipulate suggestions on how to transfer this experience to the development of new curriculum disciplines.
How do we usually trial new elements in teaching chemistry and justification for an alternative approach proposed?
Traditionally, new elements of teaching in chemistry are trialled ex-situ, i.e. outside the regular teaching process. As an example, trialling new synthetic laboratory exercises or application of new analytical techniques for characterization are typically evaluated outside the teaching term by academic or technical staff. It is also relatively common to have students involved in this exercise in the course of research modules or throughout the work placement outside the teaching terms. Alternatively, information is gathered from the other modules or literature sources. The main advantage of this trial approach is in its simplicity: this approach does not require any changes in the teaching provision since the trial is not embedded into any teaching provision. As the trial is external to the current teaching programme, its results can be discarded, or experiments can be re-run until a required result is achieved without waiting. Besides, insofar as the trial is done outside the teaching term, it does not require significant investment of teaching time and dedication of a lecturer. If the literature sources are used as a source of information, previous experience of other lecturers can be examined, including statistical analysis and feedback from students.
A major disadvantage of this trialling approach lays in the fact that it is completely disconnected from the student environment. Indeed, if new elements of teaching provision are trialled by staff, serious doubts about the possibility of the direct transfer or adoption of these elements for regular teaching emerge. Trials done by the selected group of students during non-teaching periods raise concerns regarding the extent of representativity and the complexity of the level of exercises that might be non-adequate for a regular non-preselected group. In addition, this approach is generally not compatible with problem- and case-based learning exercises as student participation is required for a continuous period, which typically cannot be accomplished outside the teaching term or within the scope of the module in question. Finally, one should also mention that many teachers prefer not to trial new elements beforehand at all and instead introduce small changes to the taught modules, expecting students to adapt to those changes within the course and as part of learning process.
Background to our trialling model
This project introduced different elements of problem- and case-based learning as exercises to students undertaking several chemistry modules in years two to four of undergraduate taught (UG) provision as well as years one to two of postgraduate research (PhD/MPhil) provision. All these modules require the use of instrumental analytical techniques for structural characterization or identification of small organic and inorganic molecules.
Between 2015 and 2018, extensive feasibility studies for the implementation of different analytical techniques in the laboratory were undertaken; no personal or identifiable data was collected. The University of Liverpool ethics committee approval was received for all trial studies; students who participated in the two-level trial were chemistry major students at the University of Liverpool in the 2019-2020 academic year. The overall number of students registered for the five teaching modules in question was approximately 450. Among them c.5-10% of the student cohort in each module were selected randomly to ensure an unbiased representation for the study, which lasted for twelve weeks spread over two teaching terms. During the trial, the students were divided into small groups of three to five and engaged in a series of problem- and case-based exercises, whereas all other students were taught and used the instrumentation course by traditional teaching methods. Specific problems were prepared according to topics examined in the instrumental analysis course and distributed to the groups two weeks in advance of the laboratory sessions or workshops. In the process, each group organized regular meetings either presential or via web every two to three days, and students chairing each group were required to keep a detailed record of each meeting.
Data collection and progress reporting throughout trial
Data regarding student engagement, satisfaction levels, and impact of the problem- and case-based learning on their performance were extracted from the regular anonymous feedback on each teaching module. Short written extracts and citation of students’ opinion on different stages of the trial/implementation of inquiry-based learning were produced; a simplified statistical analysis was applied to all measurable data (e.g. number/percentage of students satisfied with the course, trial exercises and approach to learning). For the problem- and case-based trial in small groups in the 2019-2020 academic year, overt observations and audio interviews among participants of a trial were also undertaken. Fully anonymized observation notes collected included information on overall performance of the student assessed by the author, brief answers on specific chemistry questions regarding the topic of their study, indication of any difficulties experienced by students during exercises, and comments on their levels of engagement. Interviews undertaken included a uniformized set of questions/comments, viz. regarding the overall course of trial, main difficulties experienced by the students, students’ opinions on whether participation in the trial represented a good exercise, comments on interaction within the small group and difficulties experienced, and suggestions on whether/how new elements of the teaching trialled could add value to the current and past courses undertaken by students. For each theme identified, a quantitative mark selected by the participant in advance of the interview using the schedule form was given (ranging from completely disagree to fully agree) and a qualitative description was added during the interview by the researcher. All the marks were normalized and an average was calculated for each question. Due to the nature of the project, no control group could be selected or required as participants not engaged in trialling new methods and techniques could not provide answers on the questions posed by the researcher. All the data obtained was treated in accord with the University of Liverpool ethics policies and other applicable legislation.
Although all required ethics approvals were received prior to the commencement of this study, it is important to emphasize the researcher’s responsibility to comply with the ethics principles in the course of the study, to evaluate the potential for harm to arise and to ensure that all the measures are in place to prevent this research from negatively affecting participants. All the students registered for the module and those who were selected for the trial were treated equally following the approved ethics protocols.
Results and discussion
While traditionally, new elements of teaching in chemistry are examined ex-situ, i.e. outside the regular teaching process (see previous sections), we envisaged a different approach to trialling new elements of problem- and case-based learning consisting of two levels, that are hierarchically interconnected (
Two-level model for the trialling of problem-based learning (PBL) and case-based learning (CBL) in analytical chemistry.
Level 1. In-situ trial
The initial level of the trial consists of the following approach modelled during three main synthetic chemistry practical modules of undergraduate provision. As a background, in the context of a large chemistry laboratory, students undertake most analytical characterizations of synthetic products primarily independently. For instance, characterization of the purity of pre-separated organic compounds is done using gas chromatography as a part of regular activities in the organic chemistry lab. Under normal conditions, each student undertake the preparative and analytical characterizations individually.
In our trial approach, randomly selected students from this module were divided in groups of three to five and asked to undertake the characterization analytical problem as a team instead of performing the work individually. As a part of this team exercise, students were asked not only to apply the standard gas chromatography techniques for analysis but to solve this problem given by following a six-step procedure common for analytical chemistry (Evans & Foulkes, 2019). This six-step procedure requires students to learn the justification of the technique, enquire how the instrumentation works, provide a brief description of the analytical procedure, and identify the limits of application of this technique to both current work and in the general context of chemistry. Students were also asked to suggest an alternative to the gas chromatography technique available in the laboratory, i.e. gas chromatography coupled to mass-spectrometry.
The student response was primarily very positive, with c.90% fully engaging with the exercise. To work as a team, students nominated a chair of the group to oversee communication, group activities, and organization. Most of the preparative work, analysis of results obtained and preparation of the report for marking were undertaken by students together outside the regular class activities. In the course of in-class activities, during report preparation and marking exercises, students were observed, and their performance was recorded. In our trial, students were marked individually assuming a similar contribution of each participant to the group activity. Upon completion of the entire lab course, students were interviewed, and their feedback was additionally analysed.
The students interviews and their feedback shed light on student satisfaction, problems experienced and gave an idea on the implementation of the new exercise and techniques. First, students are likely to be engaged with small group exercises if they feel that the additional time required will bring clear benefits to their curriculum. Second, cooperative work undertaken by students requires good communication within the group and good compatibility between students. Among the feedback received, 85-90% of students felt positive about being engaged with the problem- and case-based activities within the modules trialled. There were no direct disadvantages reported by students, although 45% of students indicated that this approach is significantly more time-consuming and for a wider application, benefits of problem- and case-based learning should overpower disadvantages associated with time consumption. Additional notes from staff suggested that this trial model is easier to undertake, and it is significantly more representative than an ex-situ approach.
From this level of trial, the most important information obtained concerns the feasibility of the implementation of problem- and case-based teaching elements. In addition, examining new analytical techniques and instrumentation gives an opportunity to revise the laboratory projects and connect these activities to other analytical chemistry curriculum disciplines.
From our perspective, the main advantages of this trial route were evident upon observation of the students. Firstly, it is clearly compatible with case-based and problem-based analytical tasks within the current module structure and without affecting the remaining student cohort. This approach can be easily organized in the course of different practical modules, and not exclusively analytical chemistry ones. Secondly, the results of the trial are representative and inclusive, as students are randomly selected, with outcomes yielding convincing evidence which might be helpful during the design or re-design of new curriculum disciplines. A good comparison of activities of students undertaking this trial versus regular groups can also be done in a direct way. Separate feedback can be easily recorded for both trial and control groups. Thirdly, if the group exercise fails for some reason, an easy fallback is guaranteed as only relatively minor changes to the regular exercise and programme are undertaken. Finally, from our experience, students feel more motivated to do activities not out of a textbook, frequently out of curiosity, gathering additional skills such as experience in group work, cooperative approach to study, and knowledge of new techniques, thus improving their own experience.
Certain disadvantages of this trial model should also be acknowledged. This trial method adds more to the workload of both the busy students and staff. It is compatible with practical work but does not fit directly to the lectures and workshops without significant changes in the module structure. Additional attention of the lecturer is required in the course of the small group exercise; hence, this trial approach will work well with a relatively limited number of small groups without requirements for the additional resources, e.g. staff time.
Level 2. Undergraduate and postgraduate partnership
This level of the trial was evaluated during workshop activities on the postgraduate research (PhD/MPhil) module. As background, in the context of the postgraduate research module, students sit a set of lectures on applied analytical chemistry for structural elucidation. In addition to lectures, the module includes a series of workshops undertaken in small groups incorporating elements of case- and problem-based learning. While most students on this module are PhD students, in the last two years postgraduate (PG) and final year undergraduate (UG) students were also allowed to sit this as an option.
In the context of workshops, students traditionally work in class on solving and a reflective analysis of case-based scenarios in small groups. When undergraduate and postgraduate students joined the exercise, an idea to produce a mixed group emerged: all the PG and UG students were divided into groups of three to four chaired by one PhD student. Both PG/UG and PhD students were sitting this exercise as equal partners and their activity was marked as a group. Although this trial method was specifically developed for the PhD module we teach at the University of Liverpool, a compatible approach was also trialled, when an extra PhD or MSc student was invited to chair the group of undergraduate students as a part of professional experience. A later approach is to some extent related to peer-assisted learning widely adopted at the university level (Bugaj et al., 2019; Sedghi & Lunt, 2015).
Different elements of problem- and case-based learning were trialled using undergraduate and postgraduate partnerships. We were able to learn more about acceptance of these methods of active learning, to get an insight on typical problems experienced by both undergraduate and postgraduate students, and to gather information on the efficiency of these methods of teaching and resources required. As the trial is done in parallel to the remaining non-mixed groups, immediate comparison can be done upon observation and analysis of feedback. Furthermore, it was clear to us upon observation that this method of trial can be easily scaled up, and indeed the entire class can be organized in mixed groups if there is a suitable ratio of undergraduate and postgraduate students.
The main advantages of this method of a trial are recognized as follows. Firstly, this approach is directly compatible with problem- and case-based learning of a relatively broad range of complexity. Indeed, it may start from giving a relatively simple case study with a known solution to students, gradually developing to a complex unsolved problem, e.g. originating from industry or academic research. The partnership approach allows for a fast assessment of new active learning elements with fewer resources available as a part of the chairing/mentoring job is undertaken by the postgraduate partners. It also helps to reduce the requirements for staff time during both the trial and subsequent implementation of the problem- and case-based learning that is recognized as one of the major drawbacks of these active learning approaches. Here, students’ performance is clearly linked to staffing levels and levels of engagement and preparedness of postgraduate partners (Wijnia, 2016). The importance of these aspects should not be underestimated and significant arrangements should be undertaken if the results of the trial are considered for the implementation during curriculum redesign (Caukin, Dillard, & Goodin, 2016). Secondly, trialling these elements in partnership allows for the acquisition of additional learning skills. Hence, undergraduate students develop their presentation skills while postgraduate students practice chairing/mentoring procedures and group management. The development of these additional skills is of significance for future employment and should also be considered as learning outcomes and skills during module design. Thirdly, trialling problem-based methods in partnership allows for the improvement of student motivation and attendance to workshops. Indeed, a survey among undergraduate students indicated that 95% feel more motivated to attend workshops compared to 75% when non-mixed groups are considered. Finally, the results of this method of trialling elements of problem- and case-based learning can be directly transferred to the curriculum design keeping the benefits and working on disadvantages at the same time. Notes from teaching staff suggested that this trial is easier to undertake and is also significantly more representative than an ex-situ approach.
Certain disadvantages of the partnership should also be recognized. The main limitation is the requirement to have postgraduate students willing to participate in this exercise, as this approach adds significantly more to the workload of both undergraduate and postgraduate partners. Preparation of postgraduate students and their engagement with activities is also of great significance. In addition, our approach was primarily developed towards workshops, and further studies for its feasibility towards trialling lectures or practical work are required.
A couple of quotes from the students’ interviews summarize our findings from the trial:
‘Doing new analytical exercises in the course of the regular laboratory modules provides clear benefits to my curriculum and professional development. I can envisage learning these analytical techniques further in the course of my graduation project.’
‘Replacement of traditional written homework with the work in a small group helped me to integrate better within the student cohort. The cooperative work is also easier to complete rather than when the work is done individually.’
‘I enjoyed working in a small group although we needed to change a group chair in the course of the module. Perhaps a little push and better instruction are required at the beginning.’
Application of the trial model developed and transfer towards curriculum design
As the last step, we wanted to use the outcome of the trial as an aid for curriculum design. We envisaged that the results of the in-situ trial could be transferred to practical work while the results of the undergraduate and postgraduate partnership provide a solid base for the implementation of problem-based and cooperative activities in workshops. Two new taught modules, incorporating techniques and experiments trialled by students in the course of this study, have been designed. Case- and problem-based learning examples worked on were further used as examples for the undergraduate teaching via lectures and workshops. We have also recognized that the mixed undergraduate and postgraduate partnership is a viable model for postgraduate research provision and is being further used.
Analysis of students’ interviews and their feedback suggested that they are likely to be engaged in small group exercises as they feel that the additional time required is clearly beneficial for their curriculum, and allows for the development of additional skills (85%). A small number of students (c.10%) raised a concern that the cooperative work undertaken by them requires good communication within the group and good compatibility between students. There were no direct disadvantages of the application of case- and problem-based learning reported to us so far by students sitting new modules, although 40% of students indicated that this approach is significantly more time-consuming and for a wider application, benefits of the problem- and case-based learning should clearly overpower time constrains.
The majority of literature sources agree that the incorporation of active learning principles into teaching improves student learning and their motivation (Darling-Hammond et al., 2019; Gleason et al., 2011). While benefits of the application of problem- and case-based learning into teaching chemistry are acknowledged, their implementation remains insufficient, driven primarily by the requirements for additional resources to become available, staff training, and lack of trial models.
In the course of our study, we have developed and introduced the two-level system for trialling elements of the problem- and case-based learning. The advantages of this trial model are examined in the previous sections, and herein, we would like to stress one further outcome. It is known that an additional barrier to student learning in instrumental analytical chemistry arises from the initial negative attitude towards complex instrumentation subsequently affecting students’ motivation. Our trial study indicates that negative impressions can be effectively counteracted by transforming rather regular ‘passive learning’ exercises into cooperative group work. The importance of the social interaction within the students’ group and with the teaching staff highlights the significance of timely pedagogical training for the course staff. It is important to stress that the good acceptance of new elements and ways of teaching by students might be related to greater attention and support from the tutors offered during active-based learning exercises, in particular, when done in small groups.
Owing to the advantages and success of this trial approach, its outcomes were used for the development of two new undergraduate and one postgraduate analytical chemistry modules. Further studies in this direction aiming to identify other areas of undergraduate and postgraduate provision where the application of problem- and case-based learning can be beneficial, and also evaluating the benefits that implementation of problem- and case-based learning provides to the teaching of analytical chemistry are currently underway in our group.