Student-centredness in physics laboratory teaching sessions

This is a self-archived version of an original article. This version may differ from the original in pagination and typographic details. Author(s): Title: Year: Version: Copyright: Rights: Rights url: Please cite the original version: CC BY 4.0 https://creativecommons.org/licenses/by/4.0/ Student-centredness in physics laboratory teaching sessions © 2023 the Authors Published version Lehesvuori, Sami; Lehtinen, Antti; Hämäläinen, Raija; Maunuksela, Jussi; Koskinen, Pekka Lehesvuori, S., Lehtinen, A., Hämäläinen, R., Maunuksela, J., & Koskinen, P. (2023). Studentcentredness in physics laboratory teaching sessions. Learning, Culture and Social Interaction, 43, Article 100773. https://doi.org/10.1016/j.lcsi.2023.100773 2023 Learning, Culture and Social Interaction 43 (2023) 100773 Available online 24 October 2023 2210-6561/© 2023 The Authors. Published by Elsevier Ltd. This is an open access article under the CC BY license (http://creativecommons.org/licenses/by/4.0/). Full length article Student-centredness in physics laboratory teaching sessions Sami Lehesvuori a , b , * , Antti Lehtinen c , Raija H¨ am¨ al¨ ainen d , Jussi Maunuksela e , Pekka Koskinen c a University of Jyv¨ askyl¨ a, Centre for Multilingual Academic Communication, The Department Education, Faculty of Education and Psychology, P.O. Box 35, 40014 Jyv¨ askyl¨ an Yliopisto, Finland b University of Johannesburg, The Department of Science and Technology Education, P.O. Box 524, Auckland Park 2006, South Africa c University of Jyv¨ askyl¨ a, The Department of Physics, P.O. Box 35, 40014 Jyv¨ askyl¨ an Yliopisto, Finland d University of Jyv¨ askyl¨ a, The Department of Education, P.O. Box 35, 40014 Jyv¨ askyl¨ an Yliopisto, Finland e University of Jyv¨ askyl¨ a, The Department of Teacher Education, P.O. Box 35, 40014 Jyv¨ askyl¨ an Yliopisto, Finland ARTICLE INFO Keywords: Student-centredness Communicative approaches Teaching assistants Pedagogical link-making Instructional dialogue Dialogicity ABSTRACT There is a call for more interactive and student-centred pedagogy in higher education. This also concerns physics laboratory work, where student investigations are too often passive repetitions of close-ended tasks with little guidance from teaching assistants. To address this gap, a laboratory course was designed to enhance active student participation and interaction between students and teaching assistants. A seminal part of the course was the whole-class teaching sessions within which students had the opportunity to reflect on and orientate towards experimental work. Whole-class teaching sessions of four physics laboratory teaching assistants were carefully explored to determine how student-centredness was apparent during these sessions. Particular attention was given to the interactions and communication between teacher assistants and students. The results revealed different ways in which student-centredness can be facilitated in physics laboratory settings through communication, including dialogic elements. These elements consisted of eliciting students' ideas and explicitly linking their experiences to the discussions. Teacher assistants with a pedagogical background implemented dialogic communicative approaches when orchestrating instructional dialogue and linking different activities. Implications for teacher assistant training are discussed. 1. Introduction Recently, there has been a call to shift from closed ‘cookbook’-style physics laboratories (labs) to including some open-ended elements (Smith & Holmes, 2021). Although they may have their place for example in more technical and hands-on training, following detailed steps in a lab task aligns with passively listening to a lecture. Lab work should involve students in designing investigations, formulating explanations, developing models, and expressing and justifying their ideas. This kind of activity is more interactive and situated by nature, enabling students to perceive the value and meaning of the tasks they perform (Sadler, 2009). Although its benefits have been acknowledged (Wong & Chapman, 2022), the research on interaction and interactive pedagogy in higher education (HE) is * Corresponding author at: University of Jyv¨ askyl¨ a, Centre for Multilingual Academic Communication, The Department Education, Faculty of Education and Psychology, P.O. Box 35, 40014 Jyv¨ askyl¨ an Yliopisto, Finland. E-mail addresses: [email protected] (S. Lehesvuori), [email protected] (A. Lehtinen), [email protected] (R. H¨ am¨ al¨ ainen), jussi. [email protected] (J. Maunuksela), [email protected] (P. Koskinen). Contents lists available at ScienceDirect Learning, Culture and Social Interaction journal homepage: www.elsevier.com/locate/lcsi https://doi.org/10.1016/j.lcsi.2023.100773 Received 26 April 2023; Received in revised form 3 October 2023; Accepted 11 October 2023 Learning, Culture and Social Interaction 43 (2023) 100773 2 still an under-researched area. In HE, TAs play a crucial role in acting as a bridge between students and university teachers. Generally, the interaction between students and TAs needs to be investigated from various dimensions, including e.g., their roles, responsibilities, and the nature of their relationship. TAs are typically undergraduate or graduate students who assist with teaching and who may face multiple challenges in their roles (Riese et al., 2021). Even though the smaller competence gap between the TA and the students can benefit both learning and motivation (Dawson et al., 2014) and many TAs plan to continue their academic careers (Lin et al., 2013; Miller et al., 2018), they often have limited or even non-existent educational training (Luft et al., 2004) which can cause issues during, for example, assessment of student learning (Wald & Harland, 2020). Subject departments' often offer TA training courses that might focus simply on classroom management or pedagogical content knowledge (Hammrich, 2001; Hollar et al., 2000). There is a need to develop TA training as these programs often result in inconsistent learning experiences and thus in a lower quality of teaching for the students (Hughes & Ellefson, 2013). TAs' responsibilities in science subjects often lie in guiding lab work and/or recitations. In the department where this study takes place, TAs have been used to supervise lab work for many decades because it offers the TAs opportunities to gain teaching experience and is also financially sustainable for the department. Recently, the lab courses at the department were renewed to include also whole-class teaching and not simply supervision of student experimental work. Whole-class teaching session refers to an instructional activity which is orchestrated by the teacher with possibility for all students to participate in and elaborate on. These TA-orchestrated sessions offered a forum for students to reflect and orient towards forthcoming lab work, which also enables research on how interactions take place in renewed settings. This study applies theoretical frameworks that address instruction and interaction to HE (see studies in primary and secondary contexts, e.g. Hennessy et al., 2020). Especially exploration of TA and student interaction is still needed in order to understand the nature of communicative approaches taking place in this setting (Mortimer & Scott, 2003). One challenge for HE is how theoretical perspectives and derived methodological approaches fit in teaching and learning subjects such as physics. For this purpose, frameworks of pedagogical link-making (Scott et al., 2011) and communicative approach (Mortimer & Scott, 2003) are applied in studying the interactions in a physics lab course. These frameworks originate from sociocultural theory (Vygotsky, 1978), which highlights the importance of interaction. Sociocultural perspectives of teaching and learning emphasise that learners acquire new strategies and knowledge as they discuss topics among the whole class and in peer interactions (Littleton & Howe, 2009). Especially whole-class discussion has been shown to lack in the communicational spectrum, while being dominated by lecturing and transmission modes of teaching (Myhill, 2006). The prevailing forms of communication could be challenged through questioning strategies that stimulate idea sharing (Mortimer & Scott, 2003) or productive thinking facilitating student reasoning and argumentation skills (Chin, 2007). In this study whole-class lessons cover common class-sizes in Finnish education (Lehesvuori et al., 2013) with exclusion of mass lectures. Studies that have delved into university physics student interactions, for example, the way physics students interact in groups when engaging in inquiry tasks (L¨ ams¨ a et al., 2018), have been more focused on macroscale temporal scrutiny of the changes in collaboration activities. The extensive work around more student-centred approaches such as inquiry and problem-solving strategies in groups has been rationalised by so-called 21st century skills (Berge & Danielsson, 2013). The current reform of physics labs calls for an emphasis on developing experimental skills (Walsh et al., 2022) and the inclusion of open-ended elements to increase student agency (Kalender et al., 2021). 1.1. Student-centredness in science education Lecturing has been recognised as a traditional teacher-centred method, especially in HE (Marmah, 2014), and teachers have been quite reluctant to shift towards more interactive pedagogy (Chadha, 2020; Plush & Kehrwald, 2014). Traditional transmission modes of teaching have been criticised for limiting learners' opportunities to share their everyday conceptions (e.g., Lehesvuori et al., 2018; Driver et al., 1994; Lemke, 1990), and yet they continue to dominate science subjects (Chadha, 2020; Mercer et al., 2009; Wells & Arauz, 2006). Despite the need for teacher control and support when navigating learners in and through science, the overuse of teacher-centred and authoritative approaches may result in learners losing interest in science (Lyons, 2006). There is evidence that student-centred approaches within teacher-orchestrated classroom interactions lead to improved motivation towards learning science (Kiemer et al., 2015). University students can struggle with their self-conceptions and identity, especially in the beginning of their studies and subjects like physics (Irving & Sayre, 2013). In order to integrate students as active agents in their study field, student-centred approaches that initiate student participation through talking and ‘making’ science should be practiced (Peters, 2010). This could foster the formation of a self-concept as a scientist and further integration into the community (Jansen et al., 2015). Letting students engage in decisionmaking in the lab via open-ended elements results in more expert-like beliefs about experimental physics (Wilcox & Lewandowski, 2016) and in an increase in student agency during the lab course (Kalender et al., 2021). Inquiry-based teaching and learning have been linked to student-centredness (Anderson, 2007); however, merely doing closed-ended experiments cannot be counted as scientific inquiry (Smith & Holmes, 2021). Instead, if inquiry is integrated with authentic reasoning and argumentation (Lehesvuori et al., 2017), the conditions for establishing student-centredness are made possible through dialogue (Wells, 1999). Little is known about how these aspects are discussed in HE and science instructional labs, especially with TAs. Stang and Roll (2014) found that the number of interactions that TAs had with students in the lab was positively associated with students' engagement in the lab. Their study did not elucidate the types of communication associated with these interactions. Wan et al. (2020) characterised the interaction patterns of TAs in a physics instructional lab setting into three profiles: the group-work facilitators, the waiters, and the whole-class facilitators. 1.1.1. Different forms of student-centredness Student-centred approaches have also been highlighted in educational policies (MoE, 2008), curricula (REMOVED FOR REVIEW), S. Lehesvuori et al. Learning, Culture and Social Interaction 43 (2023) 100773 3 and university strategies (REMOVED FOR REVIEW). Student-centredness can be carried out in instructional approaches (Lehesvuori & Ametller, 2021) through shared responsibility and ownership (Lehesvuori & Ametller, 2021; Enghag et al., 2007) or self-directed learning (Schweder & Raufelder, 2022). Based on the literature and our previous studies, some of the presented dimensions formulated in the context of this study are as follows: ● Instructional settings and approaches: Student-centredness can be facilitated through activities that support peer interaction and group discussions, and, in general, interactions within students can express themselves during exploration and inquiry of ideas (Wells, 1999). ● Shared responsibility: Student-centredness manifests in shared responsibility, which means that students have freedom of choice to material, methods, and content. ● Shared ownership: This can be conveyed through explicit notification of students' views and efforts (Enghag et al., 2007). That is, students' role as makers, and not only as re-creators, of science is acknowledged. Shared ownership can manifest, for example, in pedagogical links that enhance continuity and emotional engagement (Lehesvuori & Ametller, 2021; Scott et al., 2011). ● Communication: Students are given space to express their thoughts without fear of being wrong, and these are also explicitly taken into account. Students have possibilities for authentic reasoning and argumentation, which is often facilitated through a dialogic communicative approach (Mortimer & Scott, 2003). Whereas this study addresses communication more on surface-level rather than providing information beyond behavioural engagement, it has been shown that especially problem-solving group discussions are potential for cognitive engagement enhancing learning (Tullis & Goldstone, 2020). And, although peer interaction is fundamentally discussed as influential especially with challenging tasks, it does not diminish the teacher's role in orchestrating post-peer-discussions and conclusions in whole-class discussions (Lehesvuori & Ametller, 2021). 1.2. Pedagogical link-making and communicative approach Pedagogical link-making addresses the ways in which teachers and students make links between ideas and science concepts within instructional dialogue. Pedagogical link-making encompasses, not only how science content is discussed (Lehesvuori & Ametller, 2021; Scott et al., 2011), but also the ways students are emotionally engaged in learning processes through linking their experiences and ideas to knowledge building (Barreto et al., 2021). In relation to both knowledge building and emotional engagement, different ideas and experiences are linked in time through facilitation of continuity (cf. Jakobson & Axelsson, 2017). The expected interplay between viewpoints of teacher and students can be seen as the driving force for more dialogic communication. Different forms of link-making have been shown to also correlate with physics learning. That is, the way physics concepts are linked in their temporal surroundings (Schlotterbeck et al., 2020) as well as between contexts (Viiri & Helaakoski, 2014) makes a difference. Concerning this study, striking the balance between introducing scientific content and considering student views takes place through pedagogical link-making and Fig. 1. Quadrant about how student-centredness can be facilitated through communicative approaches. S. Lehesvuori et al. Learning, Culture and Social Interaction 43 (2023) 100773 4 facilitation of different communicative approaches (Mortimer & Scott, 2003). Mortimer and Scott's (2003) framework for Communicative approaches differentiates the typical transmission modes of teaching from more student-centred approaches conveyed through more interactive forms of communication and instructional dialogue (Lehesvuori et al., 2018). The framework also enables understanding what counts for meaningful learning science (Scott & Ametller, 2007). The framework consists of four categories generated from a combination of two dimensions: interactive/non-interactive and authoritative/dialogic. Interactive talk allows students to participate, whereas non-interactive talk is of a lecture type, and whereas the dialogic approach takes account of diverging ideas, the authoritative approach focuses on a specific point of view, usually the scientific view, controlled by the teacher. Although dialogicity can be a shortcut to student-centredness (Lehesvuori et al., 2018), in light of the presented literature, we derive a quadrant introducing examples of how student-centredness can be reached in all four communicative approaches (see Fig. 1). In terms of meaningful learning of science (Scott & Ametller, 2007), it can be argued that all four communicative approaches play a role in student-centredness when the aim is to learn science. Complementing Fig. 1, the communicative approaches and examples of their relation to student-centredness: ● In the question-answer routine of the authoritative and interactive approach, students' responses are often evaluated, and the teacher neglects diverging ideas. The authoritative approach focuses on scientific points. Student-centredness can be present, for example, in diagnostic questions, which can be exploited in group discussions within students to justify and reason their selections. Thus, the interactive authoritative communicative approach could lead to potential, even dialogic, argumentation (Author et al., 2017). ● The dialogic and interactive approach explores students' ideas (e.g., everyday views) but has no evaluative aspect. In Mortimer and Scott's (2003) categorisation, the dialogic approach is considered when the teacher is not trying to achieve a specific point. Rather, the teacher attempts to elicit the students' points and works with contrasting views. This aligns with student-centredness by providing spaces for different ideas. ● In the dialogic and non-interactive approaches, the teacher focuses on contrasting points, such as students' everyday views, and moves on to present the scientific view. Even though the teacher lectures, diverging ideas are discussed (note: dialogic nature). Although this is the most infrequent communicative approach (Lehesvuori et al., 2013), it has major potential to embrace shared ownership, as the teacher explicitly considers student efforts and ideas. This can be essential when building links between preconceptions and to-be-learned content. ● In the authoritative and non-interactive approach, the teacher presents scientific content by lecturing and takes no account of contrasting points of view. Although often linked to teacher-centredness when overused, the teacher's lectures and presentations correspond to meaningful learning of science in terms of providing students with the necessary knowledge to pursue their individual and group work. The division between different approaches should not be seen as dichotomous (Scott et al., 2006); rather, approaches seed each other in a cyclic continuum (Lehesvuori et al., 2013). As suggested by Scott and Ametller (2007), after scientific content has been introduced via authoritative approaches, students should be given opportunities to adopt this content in their discussions and talk. Conversely, if students' ideas have been collected with low interanimation of these ideas, then these ideas should be linked to scientific ones via more authoritative approaches led by the teacher as a part of knowledge building processes. An example of a teaching strategy integrating different teacher-orchestrated instructional activities and communicative approaches could include the following phases and shifts between them: 1) delivering necessary information to set up the lesson (authoritative and non-interactive); 2) collecting student ideas and/or pre-conceptions (authoritative and interactive); 3) using collected information to set up dialogic discussions and argumentation (dialogic and interactive); 4) taking explicitly into account student ideas when building links between students' and science's points of view (dialogic and non-interactive); and 5) establishing scientific conclusions (authoritative and non-interactive). The order may vary; for example, the lesson may begin by opening dialogic space when mapping students' everyday views. This study adapts the framework to interpret the instructional activities and interactions taking place in lab course whole-class teaching sessions. The framework offers a straightforward approach to exploring whether student-centredness is taking place in interactions and especially communications orchestrated by the lab TAs. Although authoritative approaches typically dominate teacherorchestrated communication, any instances of implementing the dialogic approach could serve student-centredness in temporal surroundings across and through links between communicative approaches (Lehesvuori et al., 2013). 1.3. Research questions The study aims to determine how different forms of student-centredness manifest in physics lab whole-class teaching sessions. In particular, the role of communication is explored through the following research questions: How do TAs enable student-centredness through: a. different forms of pedagogical link-making? b. different forms of instructional dialogue? The findings of this study will provide new information about how physics lab TAs enhance student-centredness in a renewed physics lab context when orchestrating whole-class teaching activities and communication. Furthermore, the implications for TA training are discussed. S. Lehesvuori et al. Learning, Culture and Social Interaction 43 (2023) 100773 5 2. Methods 2.1. The context and the participants A reformed first-year physics lab course was developed in <REMOVED FOR REVIEW>. The participant students (N =70, see Table 2) are mostly physics majors, although sometimes also chemistry, mathematics and other STEM related majors may take the course. The course includes no lectures and no self-study material. The plan was to engage students in more active learning involving them in designing measurements, peer discussions, and iteration of the technology-enhanced investigations. Previously, the course included students' doing experiments and measurements in lab settings under the supervision of a TA. This supervision was related to technical support and to checking that measurements had been made and that the results were suitable for analysis. The students were expected to mostly self-study the necessary content and skills for the often verification-based lab tasks. The reformed course focuses on developing students' experimental skills with open-ended elements in each task, instead of covering the content of the lecture courses. The course has fixed weekly four-hour lab sessions with TAs, who now have more responsibility for teaching the necessary content and experimental skills, as well as guiding the students through the experiments and measurements. TAs' duties consist of teaching the weekly sessions, grading and giving written feedback to the documents returned by the students (e.g., presentations and brief lab reports) and participation to the weekly reflection and planning meeting with faculty members. Concerning this study, in particular, TAs participated a planning meeting a week before where everyone was walked through the session contents, and the TAs received ready-made slides to build their teaching around. In the one-hour pre-experimental phase, the TAs familiarise the students with the experiment they are about to conduct. Further, the necessary content related to, for example, error analysis is presented in this phase. The two-hour experimental phase involves the design and performance of the actual measurements. The one-hour post-experimental phase is reserved for data analysis and reporting of the results. Despite the presented structure, there is flexibility for students to pace their investigations. The TA-orchestrated wholeclass preand post-experimental phases are expected to play a specific role in both practical orientation and deeper reflection on the explored phenomena (Rollnick et al., 2001). Furthermore, in this format, there is potentially more student–teacher interaction involved, which necessitates considering pedagogical approaches when orchestrating activities, as well as educational dialogues. Compared to previous models (cf. Koskinen et al., 2018), student ownership of learning and possibilities for the adaptability of the time and place are decreased (cf. Enghag et al., 2007), as student-centredness is conveyed through versatile onsite communication (Lehesvuori et al., 2018). The information in Table 1 for background information was collected through personal interviews with the assistants (second Author). TAs were asked about their previous background as TAs, their participation in TA courses, and their personal motivation to be TAs. All names presented in the article are pseudonyms. In <COUNTRY REMOVED>TAs have usually finished their bachelor's degree and are continuing in their master's degree studies (see Table 1). Another group that often serves as a TA is PhD students (see Table 1). Master's level TAs are paid by the hour and PhD level TAs teach as a part of their PhD researcher contract. Although TAs may not have taken part in pedagogical studies, some departments organise TA training. TA training is important for university-level science teaching overall, since many TAs are aiming towards academic careers (Lin et al., 2013). Whereas the Table 1 provides the background information of the TAs, the main data consisted of video-recorded whole-class teaching sessions of four TAs (1 session per TA) preluding measurements. Five TAs assigned for this study, yet one TA was unable to keep his video recorded session. The focus in the lab session analysed was on comparing and pooling measurements together, finding outliers, and developing the measurement setup. This session was chosen because it potentially included whole-class teaching connected to the previous week's lab work, in which students used their mobile phone acceleration sensors to measure a certain distance in steps and metres. The data from the previous lab sessions were collected and compiled to be used for the whole-class teaching session, including discussion, tasks about errors, outliers, etc. Thus, the setting enabled student-centredness, as the students' measurements were the starting point for the teaching and group discussion tasks. Table 1 Background information about the physics laboratory teaching assistants. Information John Mary Shelly Dora Study status 1st year PhD student Master's degree student, finalising master's thesis 2nd year PhD-student 1st year PhD student Course for assistants and/or other pedagogical studies No course for assistants. No pedagogical studies No course for the assistants. No pedagogical studies No course for the assistants. Ongoing pedagogical studies for adult education Course for assistants. Basic education studies. Discontinued subject teacher education studies. Applying for an Adult Education degree Experience as teacher and/or assistant Spring of 2019, as a laboratory assistant of physics basic studies Spring of 2019 to autumn of 2021, as a laboratory assistant of physics basic studies Since autumn of 2019 to autumn of 2022 (excluding COVID-19 lockdown), in basic and intermediate studies Since spring of 2020 (exclude COVID -19 lockdown) to autumn of 2022, in basics and intermediate studies and accelerator laboratory Personal motivation for assistant/ teaching work A colleague asked for interest Positive experiences about laboratory work as a student and likes ‘teaching kind’ of duties An email requested interest and positive experience of peers The salary and positive experiences of peers S. Lehesvuori et al. Learning, Culture and Social Interaction 43 (2023) 100773 6 2.2. Data collection Four video-recorded whole-class teaching sessions on the same topic were explored. The length of each session was approximately 45 min. The video recording was organised for sufficient collection of relevant data while minimally disturbing the execution of the whole-class teaching sessions. The camera was placed by the researcher before the teaching session began. The wide-angle camera captured both the teacher and the students. Whereas this study does not discuss the impact of videoing, prior research on video-based studies suggests that videoing have minimal to no effect on the behaviour of both teachers and students (Fischer et al., 2014). Video data was collected on-site by the first Author. He is not personnel of the Department of Physics, rather his role is in bringing pedagogical insights to further development of the course influenced and designed by the other Authors. The organisation of the datacollection could be seen as a traditional researcher-participant setting within which researcher merely observes and places no input to execution of the lesson. It has been shown that this kind of setting unlikely effects on the verbal behaviour of the participants (Samph, 1976). TAs and students were asked for their consent to take part in the study. The TAs filled in a written consent form, and students were informed about the research at the beginning of the semester, when digital consent forms were collected. In addition, the students were informed about the study at the beginning of the video recording, and they were given the opportunity to withdraw from being seen in the recording at any point of the study. The lab TAs were only informed about the general aims of the research beforehand as required in the study's ethical guidelines. 2.3. Data analysis The analysis was conducted at different levels. At the macro level, the lessons were divided into episodes. During this process, the following types of instructional activities were detected alongside paying attention to communicative approaches: ● Teacher presentation (TP): The TA presents the content and/or provides instructions for the task. The prevailing communicative approach is authoritative and non-interactive. The approach may include short exchanges and passages of interactive communicative approaches (Lehesvuori et al., 2019). ● Group discussion (GD): Students discuss a task together. The type of student–student discussion is not the focus of this study (cf. Díez-Palomar et al., 2021). Also, the framework of communicative approach is originally developed for exploring teacher-student interaction. ● Instructional dialogue (ID): The TA orchestrates interactive teacher–student interactions. Instructional dialogue can be facilitated through dialogic communicative approaches, yet there is also a place for authoritative approaches in the meaningful learning of science (Scott et al., 2006). The preliminary division into episodes was conducted in real time during the data collection. The final division into episodes was then conducted from the videos. The end of an episode can be marked by changes in activity, topic, or communication, hence at the same time signalling the beginning of the next episode. Changes in spoken language could indicate these episodic shifts, and can be often detected by contextual cues such as pauses, changes in intonation, hesitation, and linguistic marks (Polman, 2004). The codes for the instructional activities were very distinct. The structure of the lessons and codes for the episodes were discussed and confirmed by the first and second authors. First author did the initial coding in lesson notes during video recording and confirmed the structure episode by episode through the videos. The structure was then checked by the second author who prepared the reflective sessions. The examples were selected by the first and second authors, who familiarised themselves with both lesson notes and video recordings. After categorising the instructional activities at episode-level, a more in-depth and microscale analysis of the interactions was conducted for the selected episodes. The selection of the cases was made based on the differences found in the implementation of the communicative approaches (see Fig. 1). The selection followed a purposeful selection procedure, aiming to bring forth the phenomena under exploration (Patton, 2015). The approach followed a strategy for presenting counter-examples across cases (Yin, 1994). The Table 2 Types of instructional activities (TP =teacher presentation; GD =group discussion; ID =instructional dialogue; N/A =not applicable/applied; E = example). Episode John Mary Shelly Dora 17 students 15 students 21 students 17 students 1. Introduction to the day's topic and assigning task A based on student measurements TP TP TP ID (E1b) +TP 2. Task A: Group discussion GD GD (E2a) GD GD 3. Collecting ideas (N/A) (N/A) ID (E2b) ID (E2c) 4. Presentation and assigning Task B TP (E1a) TP TP TP 5. Task B: Group discussion GD GD GD GD 6. Presentation and assigning Task C TP TP TP TP 7. Task C: Group discussion GD GD GD GD 8. Instructions for experimental work TP (after which student experimental work and improved measurements using Task C outcomes) S. Lehesvuori et al. Learning, Culture and Social Interaction 43 (2023) 100773 7 selected episodes and rationales for selection are presented and organised under two main theoryand research-guided themes: pedagogical link-making and communicative approach. The selection of the examples was straightforward, as pre-designed presentation material led to a clear structure for the teaching sessions and differences manifesting merely at the communication level (Sawyer, 2004). As noted earlier, the targeted focus on wholeclass teaching sessions is also rationalised by the detectable differences in the often-narrow communication spectrum (Myhill, 2006). The chronological order of the episodes is presented in Table 2. Whereas the presentation of second theme examples follows a chronological order, the examples of the first theme show a mixed order in terms of foregrounding and highlighting the case (see findings). The in-depth scrutiny of the instructional dialogues (and teacher presentation in John's case) draws on the general principles of sociocultural discourse analysis, complemented by conversation analysis techniques. The sociocultural approach to analysis is less focused on content of language itself and more on the functions that language serves in joint activities and discussions (Mercer, 2004). The conversational analysis techniques, instead, provide ways to access data-emerging patterns (Hsu et al., 2009) or single turns, such as teacher questions and follow-ups (Berland & Hammer, 2012; Chin, 2007), with complementary attention given to multimodal features (K¨ a¨ ant¨ a, 2015). By drawing on student-centredness, pedagogical link-making and dialogic communication, specific attention will be given to any characteristics supporting these aspects to take place (e.g., TA posing open questions and exploring student ideas, see descriptions in Fig. 1). Microscale analysis and interpretation of the selected examples were discussed among all of the authors. In every phase, disagreements were discussed until a consensus was established. Overall, the procedure followed guidelines set for explorative case studies (Yin, 1994) and researcher triangulation (Miles & Huberman, 1994). 3. Findings The Table 2 reveals that the structure of the joint session followed a similar pattern in all cases. Teacher presentation of the content was followed by tasks engaging students in group discussions based on Tasks A, B, and C. The group discussions were followed by further presentations and instructions for the next steps. Exceptions in the presence of instructional dialogue were, however, detected in Shelly's and Dora's sessions. Whereas only Dora successfully challenged the prevailing authoritativeness and applied instructional dialogue at the beginning of the session when reviewing students' experiences from their previous efforts in experiments and data collection, Shelly and Dora built an episode-level communication link between the group discussions and teacher presentations. In other words, some ideas arising from the group discussions were brought to the social plane of the whole class, which was not the case in John's and Mary's teaching sessions. The episode-level overview provided in Table 2 indicates that student-centredness was facilitated through opportunities for peers to share their ideas on pre-designed tasks. This corresponds with facilitating student-centredness in instructional approaches through group discussions. Although the instructional design—that is, the prepared material and activities—also included consideration of students' previous measurements, there was some shared ownership of the content. These ideas were used in the discussion and further development of the methods for continuing measurements, which also conformed to fostering pedagogical link-making and continuity. Although student-centredness was conveyed in the design of instructional approaches and shared ownership, further exploration is needed to understand how student-centredness took place in teacher-orchestrated communications. Thus, the selected cases are explored next in order to address how student ideas were linked and brought to instruction through both aspects of communication—authoritative and dialogic. 3.1. Pedagogical link-making and different ways to extend the context The first set of examples concern pedagogical link-making, addressing different ways to extend the context: ●Example 1a (E1a) is about John's presentation about the consideration of errors in measurements. Distinct communication moments involve the lab TA linking his own experience about measurement errors in his own PhD study to the students' measurement task. Although the example highlights the lab TA's ownership of the content as well as his experiences, this form of pedagogical linkmaking was the only one of its kind in this dataset and could serve as an indicator for meaningful interactions. ● Example 1b complements E1a as a counter-example. Dora's beginning of the teaching session included a brief moment of instructional dialogue and a dialogic communicative approach implemented before the teacher's presentation. The purpose was to link the students' previous experiences to the day's activities. This corresponds to linking for continuity and shared ownership. The first example (E1a) involves John presenting the factors that can influence the measurements and cause errors. John's presentation of the prepared content is interrupted by himself as he brings up some real-life experiences about measuring: Used transcription markers: [text] =talks over, right after or simultaneously, [x] =wait time ×seconds, [text] =clarification or additional necessary information, (…) =cut-off or reformulated sentence John So here we have some outliers. And, these outliers might have an effect on the depicted values. For example, it greatly affects the mean value. Those really outlying results. One reason could be that there is something wrong with the measurement devices [reads from the slides]. The other one is that the heating or cooling of the measurement device has not been stabilised. This is very common, and in fact, it happened to me yesterday [change of tone]. I was doing neutron measurements in <PLACE REMOVED FOR REVIEW>, and we were measuring the Californium-252 source using different distances. We used a gas-filled helium-3 neutron detector. Every time we changed the distance, the counting frequency increased or decreased. Then, we noticed that (continued on next page) S. Lehesvuori et al. Learning, Culture and Social Interaction 43 (2023) 100773 8 (continued) every time we changed the distance, it took several minutes to get the results stabilised. So, we did have to wait until the results were stabilised for the exact dose rate. Or the counting frequency. After that only could you record the results. It was noticed that with lower dose rates, it took more time to stabilise. So this can be a very common reason [points to the slide]. You just had to be calm and wait for the stabilisation and only then record the results. So this happened yesterday when I visited <PLACE REMOVED FOR REVIEW >. And then the documentation can be sufficiently conducted [shifts to reading from the slide mode], or there was a pause in measurements. It can be that measurement configurations or geometry can change… [continues teacher presentation]. 3.1.1. Comments and interpretations The example begins with a teacher presentation of the pre-prepared content projected to a screen. This direct presentation is interrupted when John links his own experiences of dealing with errors in measurements and the importance of stabilising the measurements. Although this kind of link-making could support both motivation and learning (Viiri & Helaakoski, 2014), it is an opposite to shared ownership of knowledge, which was highlighted as one of the student-centred approaches. Although this demonstrates John's mastery of the content, it also underlines the asymmetry between the students and the TA. One option to bring in student experiences in terms of shared ownership could have been at the beginning of the lesson through explicit recognition of previous measurements. Besides shared ownership, this facilitates link-making for continuity (Scott et al., 2011). This is demonstrated in Dora's initiation (E1b) of the teaching sequence, in which she asks about student experiences from the previous measurement session during which she was absent: 1 Dora So, you were doing measurements with the substitute teacher. How did it go? What kinds of results did you obtain? How do you feel about last week's sessions? [4] 2 Student1 Well, some things were a bit overwhelming and other things were a bit clearer. I'm not sure whether it is one of the purposes of today to get a clearer picture of the entity? 3 Dora Yeah, sure it is. What else? 4 Student2 Yeah, it was clear when it was the peaks that were used to get the step-count. But when using Excel to get something sensible out, then it was a bit more messy. 5 Dora Okay. Yeah. It might become clearer today since the aim is to develop the methods a bit further… Whereas another example (E2c) from Dora later explores dialogicity, this example complements the above interpretations of shared ownership through opening up space for students' voice and linking their previous experiences and knowledge to the to-be-taught content. Drawing on communicative approaches, John's presentation followed the authoritative and non-interactive communicative approaches, which are demonstrated by teachers focused on lecturing and content. Dora's counter-example demonstrated elements of the dialogic communicative approach, such as collecting ideas and experiences (turn 1), probing feedback (Scott et al., 2006) and wait time (Lehesvuori & Ametller, 2021) (turns 1 and 3). Although the episode is dominated by the subsequent teacher's presentation and authoritative non-interactive approach, the beginning of the teaching sequence supports the theme of linking for continuity and emotional engagement (Scott et al., 2011). 3.2. Facilitating student-centredness through instructional dialogue The second set of examples address how instructional dialogue can support student-centredness through different communicative approaches (see Fig. 1) when connecting two instructional activities: ● Example 2a illustrates Mary's shift between two instructional activities without implementing instructional dialogue. Examples 2b and 2c are presented as counter-examples of how instructional dialogue is implemented between group discussion and teacher presentation. ● In Example 2b, Shelly poses an open question, which she then reformulates to a diagnostic one. This is one of three (see examples 1b and 2c) instances in which a space opens up for dialogue and for students to express their experiences. Although it does not lead to dialogic discussions, the example demonstrates how an interactive and authoritative communicative approach could potentially foreground follow-up dialogues and activities. Accordingly, Example 2c complements by illustrating the implementation of the dialogic approach. ● In Example 2c, Dora opens up space for dialogic discussions and orchestrates this by implementing a dialogic approach. This example demonstrates the bridging of communication between two activities: group discussion and teacher presentation. All these examples (E2a, E2b, and E2c) take place after the student group discussion. The task for the group discussion was to investigate and discuss two graphs that were formed based on the students' measurements conducted the week before. Based on group discussions, students should make notes on observations, explanations, and conclusions. The first example (E2a) concerns Mary's shift from group discussion to presenting the content from the slides: Mary Ok, now let's move on [walks to screen]. (2) So, let's have a look at when the measurements can be compared and when they cannot [continues with teacher presentation]. S. Lehesvuori et al.