Applying the Matrix Model in an English for Presentation Online Class during COVID-19 Pandemic: A Case Study of an Undergraduate Class in Thailand

During the COVID-19 pandemic, online learning was an important topic for scholars. A private university in Khon Kaen Province, Thailand followed a policy to create online courses for every subject to ensure that education could proceed effectively. To correspond with the policy, the Matrix Model was integrated with the online course development of an English for Presentation class at this private university. The Matrix Model is also known as SAMR which refers to Substitution, Augmentation, Modification, and Redefinition. The online course was presented in the third semester of the academic year of 2019 with 77 participants who volunteered to participate in this course. The research instruments used in this study were observation, surveying, and interview. The data collections were done at the beginning, during, and after the course to provide a comprehensive study of online learning. The data revealed both positive opinions and obstacles associated with this online learning. The results of using the SAMR model in this study do provide benefits to students and educators and show that 84% of the participants prefer online presentation over in-class presentation.


Introduction
Information communication and technology (ICT) has recently shifted into education to assist and facilitate learning and teaching processes at all levels of education. In the last few years, ICT has become more necessary in education as the world encounters the COVID-19 pandemic. In Thailand, COVID-19 started at the end-of-year 2019 and continued into the year 2020. The pandemic affected many educational institutions in Thailand as a classroom teaching environment could turn learning into a virus centre. This situation brought a lot of anxiety to teachers once the Thai government decreed to shut down the entire country, which meant classroom teaching and activities were forbidden. Learning online was the choice for higher education during that time for students to continue their education. The situation forced all teachers in higher education in Thailand, including this researcher, to adopt new learning and teaching technologies within a limited amount of time. Students had no chance to choose whether they wanted to take part in online learning; it was a necessary change needed for education to continue. Large universities such as Chulalongkorn University and Mahidol University, which had been preparing themselves for online learning before the pandemic, were well organized and most of their students adapted quickly. However, for some other students, change was hard. It was like an enormous wave that changed their regular learning routine in the blink of an eye.
After the government announced a Declaration of an Emergency Situation on March 26, 2020 (www.mfa.go.th), universities in Thailand were asked to adapt their teaching and learning syllabi into assignment-based study programs which require no physical attendance. To investigate the students' perspectives, a survey was done to determine the online learning readiness of students enrolled in English for Presentation in Semester 3, academic year 2019. This class was used as a case study for this research as the researcher was responsible for this class. The survey aimed to find out if the students had basic online learning tools such as computers, smartphones, and internet connections. The survey was completed within one week since not only the teacher but also students were excited and cooperated enthusiastically in this completely new type of learning and teaching. The results of this survey show that out of 77 students, there was only one student who could not always access the internet, as his/her house was in a low signal area. The issue of unreadiness was discussed in a group session in an online seminar that was run by Chulalongkorn University. Some teachers from the online seminar pointed out that many of their students do not have a computer or an internet connection. Another result from a prior study shows that some of the students had technophobia or anxiety about using technologies (Rosen & Weil, 1995) as they feared that they will make mistakes while using technologies in online learning. This kind of anxiety can occur within any age range if their experience with modern technology is limited (Khasawneh, 2018).
Though the teachers and students were not ready for online learning, this online learning is already here for us to explore and is inevitable. Thus, all higher education institutions in Thailand are in the process of accepting online learning environments. According to Allen & Seaman, 2014, teachers need to understand how to teach online, and they must be able to deliver quality courses and satisfaction within a teaching online environment. However, some educators doubt if this online learning can be as effective as in-class learning and whether the teachers and students are ready for these changes. Over the past two decades, there have been several studies regarding online learning (Abe, 2020;Kang et al., 2019;Allen & Seaman, 2017;Puentedura, 2003) for researchers to access and prepare themselves for designing online learning courses.
Before the pandemic impacted Thailand, there were several research studies on online learning environments and self-regulated learning which show that some students lacked active self-managing skills, and some of them failed in an online learning environment (Cheng, 2011;Suanpang & Petocoz, 2006;Tsai, 2010). However, there is little research on transforming traditional classrooms into online classroom environments in Thailand. Therefore, this study seeks to fill this research gap. In this English for Presentation class the teacher adapted the matrix model (SAMR) which refers to substitution, augmentation, modification, and redefinition (Puentedura, 2003) into online course planning and teaching. This study aimed to evaluate the students' opinions toward this online learning program.

Purpose
The purpose of the study was to evaluate students' opinions toward this SAMR model-based online learning program for undergraduate students at a private university in Khon Kaen Province, Thailand during the COVID-19 pandemic.

Research Question
What were the students' opinions toward this SAMR based online learning during the COVID-19 pandemic?

The Matrix Model
This model was designed by Puentedura (2003) to be used as a guideline in developing and designing online courses to succeed in existing pedagogical practice. It focused on three aspects of pedagogical practice (tool, content, and interaction). All these three aspects were used. Technologies such as computers were used as learning tools and course content delivery, online platforms were used to store content, and online applications were used to interact with students during teaching and learning processes. Technologies in this process function as an assistant for teachers to help them achieve their teaching purposes effectively.
There are four stages in the model known as SAMR: substitution, augmentation, modification, and redefinition.
(1) Substitution is when technology resources replace the old teaching methods. (2) Augmentation is when diverse sources are added to the learning. (3) Modification is when students access different media and choose necessary information for their tasks. (4) Redefinition is when students use technology to redefine their tasks. Scholars suggested that this SAMR model should be integrated into developing online learning classes (Arnold, 2019;Pfaffe, 2017;Romrell, Kidder, & Wood, 2014). Therefore, this model was adapted to be used in this study, and it was integrated into the English for Presentation class by providing a suitable online course during this pandemic. This model would be used as a guideline for the teacher to follow during the teaching and that would make this online classroom a productive course. This process will be discussed later in the section Transforming the English for Presentation Classroom into an Online Class.

Synchronous Learning Session in Online Learning
Synchronous learning occurs when students and teachers are interacting at the same time. It requires students and teachers to interact in a specific real place synchronously through an online medium. It can be utilised through online modes such as video conferencing, live chatting, and live-streaming lectures. Synchronous lessons give teachers and students chances to actively discuss and give immediate feedback. This type of synchronous session combines face-to-face activities with online instruction (Boelens et al., 2017). This type of teaching is suitable for teachers who are familiar with actual interaction (Bower et al., 2015). This is a way to begin if teachers are making a transition from classroom teaching into an online setting. A study by Martina, Ivica, and Chee Kit (2020) suggested that teachers must choose adequate computer-supported collaborative learning for synchronous lessons with adequate design and task difficulty levels.
Synchronous learning enables teachers and students to experience dynamic learning which allows them to ask questions and receive answers, to discuss and debate, so that the classroom will be more engaging. However, there are a couple of disadvantages to this type of learning. The schedule for this kind of learning will be rigid. If students' life schedules are unpredictable, synchronous learning may present some challenges to students. Another disadvantage is that it requires some technology to access the class such as a computer and an internet connection which may not be easily available. In this study, this type of learning was used parallel with asynchronous learning for assisting students to have opportunities to learn when they couldn't catch up with the lessons.

Asynchronous Learning Session in Online Learning
Students can do asynchronous learning at their own schedule and pace (Hrastinski, 2008). This kind of learning requires a clear self-guided lesson plan for the student to follow. It is a ready-made course that includes materials for reading, lectures for viewing, assignments for completing, and exams for evaluation. Also, students will need to have a platform to exchange and discuss ideas in a group, and a method to communicate directly with individual classmates and teachers. The advantages of asynchronous online courses are their time flexibility and their uncomplicated contents (Hrastinski, 2008). Some students often report difficulties maintaining a commitment to their online courses (Artino, 2008). A study by Singh et al. (2004) compared three forms of instructions: classroom, synchronous, and asynchronous using the same participants and found that asynchronous learning could be a useful way of learning for other learning environments.

Transforming English for Presentation Classroom into an Online Class
The English for Presentation course was converted to online teaching in the third semester of the academic year 2019. The purpose of this class is to train students to be able to use English in various kinds of presentations. Students are taught to prepare presentation layouts and be familiar with various kinds of presentation tools and applications. There are 45 hours for this class excluding examinations. The third semester usually lasts five weeks excluding examinations.
The class was held three times a week and each class lasted three hours. The course adopted synchronous and asynchronous teaching into each class. When it comes to online learning, there are many applications from which to choose. It is best to start with setting up goals or purposes of the course and then begin to explore applications that will support pedagogical practice to reach the purposes of the course (Crompton & Burke, 2020). The teacher explored several different applications and decided to choose the following applications to be used in the class. Also, the class used both synchronous and asynchronous teaching. The following chart ( Figure  1) is the model for teaching this class. It was adapted from the matrix model.

Applications for Pedagogical Practice
Eight main programs were used in teaching. The reasons that these applications were selected are because most of them are free of charge and are very productive for course management and preparation. The applications will be described below.
Line: This is the main communication application between the teacher and students in this class. The university has surveyed what is the most suitable application for students and teachers to communicate during this pandemic. The survey suggested that teachers should use the Line application as the majority of the students who took the survey selected this application over the other two applications as follows: Facebook Messenger and WhatsApp. The teacher submitted a QR Code for this class's group chat to the Registration Department of the university so that students could proceed to the next step of online learning. This group chat is also useful for announcements in class. Students can send questions directly into the group or privately to the teacher at any time.
Google Classroom: This online application was used as a substitution for classroom management. This is where students can keep track of their assignment submissions and scorings. It can be linked to many applications such as Google Docs, Microsoft Form, YouTube, Google Drive, and many more.
ZOOM: This application is for synchronous and asynchronous teaching. It is an application for video conferences that can be recorded. It can be used to synchronously share a computer screen or an iPad screen so that teachers and students can share information by writing on their devices. One disadvantage of the free version of Zoom is that if you are having more than one person in your meeting, the system will limit sessions to 45 minutes. However, 45 minutes was a suitable time to take a short break after which the class would resume.
Canva: This is an application for designing presentation slides, posters, cards, videos, and so on. It is easy to use and can be linked with Google Drive which can be linked to Google Classroom. The teacher used this application to design all presentation slides and poster announcements that were used in the class. This application has so many formats to choose which save a lot of time in designing engaging announcements and presentations. YouTube: Students used this application to upload their videos and share them with the class. The teacher chose this application because it is well known and widely used.
Microsoft Form: Microsoft Form is an application for designing and sending out quizzes and questionnaires. It is not overly complicated, and it also has useful features such as setting a time to release the quizzes, providing statistics on student answers, and having a spreadsheet that shows the results of the quizzes.
Microsoft PowerPoint: It is one of the basic programs for course preparation that many teachers already use, and the programs are already available on many computers.
Goodnotes 5: This application was used as a teaching board that teachers can use when some details need to be handwritten. This application is best with a tablet, as the device has a bigger screen than a smartphone to write on. It can also be used with slides or pdf files. That is very convenient when the teacher wants to write on the slides or the pdf files.

Population
The population of this research was 77 students from the English for Presentation class during semester three of the academic year 2019. The students are from a private university in Khon Kaen Province, Thailand. The course is an English general subject for the university. Therefore, the students are from different faculties and undergraduate levels. The researcher was the teacher who was responsible for this course.

Participants
There were 77 participants in total. This is a purposive sampling as these participants enrolled in this course. However, they were all willing to volunteer to participate in this study. Among the 77 participants, two students enrolled in this class in both online and in-class learning.

Instruments and Data Collections
There were three main instruments in this study. Each instrument was used on separate phases (see figure 2) as follows, before starting the course, during the course, and after finishing the course. Some of the instruments were used in every phase of the research. Every instrument was used with all the participants.
The observation was done daily by the researcher. It covered two phases as follows: before starting the course and during the course. The observation was done in descriptive form. This observation aimed to observe students' reactions during the online course to find out any real-time problems.
This questionnaire was for all participants. The questionnaire aimed to investigate the opinions of students toward online learning in the English for Presentation class. The questionnaire consisted of 10 questions with five rating levels of agreement. The questionnaire was given to an expert on English language teaching at Khon Kaen University to verify the content validity. This was done to ensure that the wordings and items are appropriate. Then the questionnaire was translated into Thai. All questions are required to be answered.
The interview aims to find out the differences between class learning and online learning from several different aspects such as a) experiences toward online learning, b) preferences of in-class English presentation versus online English presentation, c) advantages and disadvantages of online learning, d) preferences of in-class learning versus online learning, e) preferences of synchronous versus asynchronous learning, and f) problems that students encountered during this online learning. The interview took about 20 minutes for each interview.
There were three phases in data collection which are before starting the course, during the course, and after finishing the course. Observation was used in the first two phases by observing the questions asked by students and their reactions. Since the course was online, the only ways that students could ask questions were through sending e-mail, text messages, and phone calls. When students asked questions, the data were collected in written form.

Online Learning Experiences
The result from interviewing shows that among 77 participants, 24 students have studied online before and 53 students have never studied online before. 20 students stated that they did not want to study online for different reasons. The first reason, time, is limited for students who did not want to study online because they were working full time, so they could not effectively manage their time. A second reason cited was that students did not have effective devices for online learning. Third, some students have trouble understanding English in the online class. For the fourth reason, some students did not have the enthusiasm or motivation to study. The students also suggested some solutions of what they did to get rid of that feeling of not wanting to study online. Creating self-discipline is one way. Students would allocate their time to study online and try to be patient. Some students would create learning environments by finding a quiet and cool place to study. Also, they would study a little bit at a time, but they do not stop learning.
The interview also shows that the rest of the participants like online learning for several reasons. They viewed online learning to augment their knowledge as they can learn at their convenience times. This style of learning is suitable for people who study and work full-time. It is very accessible and fun to learn when they want and as much as they want. Some students from this group also suggested to not procrastinate starting the assignments and the online videos that the teacher assigned them to help them to complete the study in time.
Besides the results of the interview, the results from the rating scale questionnaire revealed several positive outcomes of online learning. The criteria to analyse the questionnaire results are 4.204 -5.000 Strongly Agree, 3.403 -4.203 Agree, 2.602 -3.402 Neutral, 1.801 -2.601 Disagree, and 1.000 -1.800 Strongly Disagree. Results of the questionnaire are shown in Table 1.

Preferences of In-Class English Presentation and Online English Presentation
Since this course focused on speaking and presentation, this section will be discussing the preferences of online presentation versus in-class presentation. The participants were asked to recall their common experiences when giving an English presentation in class. Then they were asked to compare this with their new experiences in online English presentations. Figure 3 shows the number of participants who prefer to give presentations online, in class, and both ways. 84% of the participants prefer to give English presentations online while 13% of them prefer to give English presentations in class, and 3% prefer both ways as the provided reasons in Table 2.

Figure 3. Groups and number of students' preferences
In this study, the participants expressed varied reasons for the preferences of online and in-class presentations. The presentation must be in English, and the topics varied based on the students' interests. The results show that presenting online creates a feeling of safe space for the students though they were being watched through the camera. The result is related to a study by Chien, S. -Y., Hwang, G. -J., & Jong, M. S. -Y., (2019) which reviewed that a self-recorded presentation video reduces students' English learning anxiety. A participant explained that when they are giving an English presentation online, they were more confident, could be themselves, and were more focused. The results of this part are shown in Table 2. 3. The lessons are easy, and the learning processes are convenient.
3. It is encouraging assertiveness when participants are speaking in front of many people.
4. Participants can practice as much as they want before presenting for real.
4. It is reinforcing the confidence of oneself.
5. Learning is fun. 5. When participants pronounce incorrectly, the teacher can correct them right away.
6. Participants can see their own mistakes and weak points. Then they can correct them before recording the video.
6. When presenting in front of the class, it takes more effort to practice. And that is part of learning.
8. Participants get new experiences. 9. Participants are more self-perseverance.
10. Participants can speak more naturally.

Advantages of Online Learning
The participants revealed several different advantages of this online learning. Many of the participants are working full-time jobs, and many of them explained that online learning benefited their lifestyle as it provides them time, a good learning atmosphere, and money-saving. The following categories were some examples of the interview data collected from this study.
Convenience: Online learning has two main types, synchronous and asynchronous, as reviewed above. This course used both synchronous and asynchronous teaching methods. Doing this, provided a backup for the students in case they missed the synchronous class. In this study, it was found that some students have difficulty maintaining a commitment to their synchronous course which is related to the study of Artino (2008). Likewise, the results of Artino's study reviewed that asynchronous learning assisted students to learn at their own pace as shown in the following statement.
"Online learning is very convenient because I can watch the lecture as many times as I want. Sometimes, I paused the video and watch it again the next day. Also, if I miss a live class, I still can watch the recorded video."

Student #5
New experience: There was one task in which students designed a five-minute video of them presenting a product in English. The criteria for this task were to speak English throughout the presentation and to make this video interesting. Some feedback from students indicated that they were happy to do this task and could apply it to their job. Moreover, a student explained that from preparing for this task, they have learned new knowledge outside the class such as tricks of making a better video, the technical vocabulary of selling a product, and so on. An example of a student's opinion is shown below "One thing I like about this class is that I get to learn how to design my presentation to be more interesting and I can apply what I learn to my job."

Student #19
Less anxious: As being shown in table 1, this online learning helps students to be less anxious once they are not in the classroom. Several research studies attempt to reduce students' anxiety in learning English by using technologies in their classes (Reinders and Wattana, 2014). The example of a student opinion below shows that the student experienced pressure from learning English in class. The follow-up questions were asked to the student to get more detail on that. The student explained that when they study in class, they felt nervous to use English because they were not confident and did not want to be embarrassed by their mistakes. Learning online makes them feel like no one is judging their English. They could speak through the microphone and show their face to their classmates, but still feel like they were by themselves.
"When I study online, I feel relaxed and no pressure like when I study English in class." Student #27 Self-paced learning: For some students who were missing the synchronous class, they still had a chance to learn from a video record of all scheduled classes, known here as asynchronous learning. The videos recorded everything that happened during the class sessions from the beginning to the end. Some students mentioned that they like this kind of learning since some of them are business owners thus everything could be spontaneous. Once a week, there were some extra learning sessions for the students to learn by themselves. These sessions were prepared by using asynchronous teaching videos which were edited before posting in the Google classroom.
It is corresponding to the result of the next part which shows that 87% of the students prefer asynchronous than synchronous learning with an example of a student's opinion down below.
"Sometimes we learned from a recorded video and sometimes we learned from live conference. I think when I learn from the recorded video, the teacher tended to explain the lesson more simply because she got to practice and screen the information before recording."

Student #67
"Online class allowed me to study when I am free from my job. I really like it since my free time is mostly in the evening. During the daytime, I spent time working on the business."

Student #9
Flexible time-management: Since the entire courses during that time were done online, time management was crucial. Students must manage their times to catch up with the lessons and assignments. Some students stated that learning online helps them be better in time management as shown below. It shows that the student acknowledged and understood the situation, thus we all were helping each other to get through this brand-new unexpected experience.
"My punctuality was improved since every assignment due date was set. And I could not negotiate with the teacher for being late. It was already too mess with the pandemic situation, so I thought I should just strictly follow the rule and well cooperate." #63 elt.ccsenet.org English Language Teaching Vol. 14, No. 9;2021 20 "Online learning makes me be more responsible because I must finish all the tasks before the deadline. My life became more organized during that time."

Student #11
Reaching teacher easily: Though this was an online course, personal conversation was not a problem, it was even easier to keep in contact with the students. The teacher set a schedule for everything including personal calls. From the observation, the teacher got more personal conversations with the students than before the pandemic. It was so convenient once the schedule was set up, for instance, when the teacher or students needed to ask questions, they just reached out on a free call, on the Line application. Below is an example of a student who thinks that communication was easy.
"Though it is an online class, I got to speak personally with the teacher conveniently."

Student #14
COVID-19 free zone: Obviously, this online course protected the whole class from contagious diseases because teachers and students were locked down at home for the whole semester. During that time, no one could enter the university except residents. An example of a student's opinion is shown down below.
"This is the perfect way to learn and teach during the pandemic. Though, I think it can also be used even after the pandemic is ended."

Student #38
Money-saving: Not travelling to the university helped students to save costs on travelling. Some students agree that they spent less money during this time. However, some students explained that they spent more money on the internet signal, electricity, and learning devices. An example of a student's opinion is shown below.
"I spent less money during this time because I do not have to travel to university. Normally, I must drive for two hours to join classes."

Student #21
Further exploring chances: Online study created a self-study environment for some students as shown in the statement below. The student showed that some extra searching on an unclear point was done to help them understand the lesson better. The student did not just learn from the teacher, but also from online sources where copious information is available for students to research. With asynchronous teaching, students could pause and search for extra information, thus the learning processes happened.
"When I learned with the recorded videos, I could pause and search more information on the topic."

Student #49
IT knowledge increasing: Though online learning seems easy for people who have some background knowledge of technologies, there is always something new to encounter. When the entire assignments must be submitted online, selecting programs or ways to submit is challenging for teachers. This course used many different programs for different tasks such as Microsoft form for quizzes and exercises, and Google forms for tasks that need to express thoughts in a written form. Since this course focused on speaking, video editing was one of the abilities that students learned.
"This is a very good chance to explore and learn how to use other useful programs such as how to edit video, and how to upload a file on YouTube website."

Preferences of Synchronous and Asynchronous Learning
This section focuses on the results of synchronous versus asynchronous learning preferences. The study shows that most of the students prefer asynchronous learning as shown in figure 4. This asynchronous preference is for both the extra asynchronous lessons and the regular classes mentioned in the previous section.

Obstacle of Online Learning
Throughout the whole semester, which was taught completely online, and because it was the first absolute online course for the students, several troubles were revealed by the students. The troubles can be categorized into four main groups. The first group is that there were too many assignments. The students explained that since the teacher had to check for the class attendance and at the end of each class, an assignment must be submitted to confirm their attendance. The second group is the lack of knowledge of how to use the programs. Some students have a challenging time learning how to use the programs such as video editor and video conferencing. The third group is the inconvenience of devices for online learning. It was reviewed that some students do not own a proper device for online learning such as a computer and a good internet signal, so when they need to submit an assignment, they must travel to places that they can use a computer with a strong internet signal. The fourth group is unable to get correct pronunciations. When students are writing their presentation scripts, many times they are using unfamiliar words from a dictionary, so they were not able to pronounce them correctly.
It is likely that the first obstacle, which is that there were too many assignments, was related to the third group since a student provided a further explanation in the interview that travelling to a cousin's house to use the computer to study and to submit the assignments made them feel annoyed though the cousin was very welcoming. This shows that this inconvenience situation interrupted the learning processes.

Observation
Before starting the course: Participants cooperated very well and seemed active with this online learning as it was the first time for most of them. A few participants reached out to the teacher saying that they were afraid of online learning because they did not know how to do it and required high assistants from the teacher. The suggestion for this phrase is that teachers should provide effective explanations on how to join a classroom and how to submit an assignment. The explanation can be a short video clip or a short PowerPoint presentation. Also, the tentative schedule for the class and the activity in the class should be informed at the beginning of the course to avoid surprise and anxiety for participants. Furthermore, it was quite difficult for the teacher to choose the appropriate applications for use in an online classroom. There are tons of interesting applications which might be useful for the class, but the teacher could not use all the platforms or applications as there was a limited of time to prepare for the course.
During the course: During the teaching period, it was found that it was difficult for the majority of the participants to shift between programs and platforms when using their smartphones because they cannot afford a computer. If the participants had a laptop computer, it would be easier for them to shift from a program to another. The suggestion for this is that teachers should select one to three programs to be used in the classroom and stick with them throughout the course.

Conclusion
Studying online during the COVID-19 pandemic was not simple for teachers and students at the beginning since it was a new experience for everyone. Like classroom teaching, online teaching requires a lesson plan, but, in addition, it is also essential to have some plans for using technology. There are a substantial number of computer applications and programs for online learning and teaching. To maximize the benefit to the students, teachers must select some suitable applications and programs for their classes. Also, the applications and programs must be used at the right moment and with the right activities. Therefore, a model was used in this study to assist teachers in planning this online course. This study investigated the students' opinions toward online learning. The Matrix Model or the model which is known as SAMR was adapted to be used in designing the online course for this study. The model facilitated online course planning to increase student benefits as shown in the results and discussion part. A considerable number of the students have positive opinions toward online learning 8% 87% 5%

Preferences of Synchronous and Asynchronous Learning
Prefer synchronous learning Prefer asynchronous learning Prefer both methods and activities which happened in this English course. According to the results and discussion of this study, it can be concluded that a) the SAMR model strongly benefits this course planning as it makes this online learning proceeded smoothly and resulted in several positive opinions of the students toward this online course, and b) there should be asynchronous teaching along with the synchronous teaching as a great number of the participants prefer asynchronous because of significant benefits. In the future, as online learning will be utilised extensively, educators should prepare for both online and onsite teaching. There is a current teaching method called hybrid which has few research studies published. For further study, it is highly suggested to explore the SAMR model in this hybrid teaching context.