Teaching involves answering students’ questions, anticipating difficulties, and dealing with unexpected situations. The science classroom can be a complex and dynamic place where unexpected situations may occur, even for an experienced teacher. For this reason, science teaching often does not proceed according to plan. Rowland et al. found that many unpredictable or unexpected moments result from students’ ideas, suggestions, questions, (un)availability of materials, and teacher insights[1]. Therefore, teachers’ ability to notice and respond to these unexpected occurrences is an important element of effective instruction[2].

Elementary school teachers experience difficulties teaching science classes for various reasons[3-5]; in particular, electric circuits are one of the most problematic topics to teach[6-8]. Generally, elementary school science is based on phenomena rather than concepts. However, in electric circuit lessons, unexpected phenomena are often observed. These phenomena tend to be difficult to explain in terms that are easy for elementary school students to comprehend. Concepts related to electricity (e.g., electric current, resistance, and electric field) are abstract and cannot be directly seen or experienced. Indeed, both elementary school students and teachers hold various misconceptions regarding circuit components such as batteries, miniature electric bulbs, and electric current[9, 10]. Efforts have been made to identify teacher misconceptions, using surveys or testing tools, in order to address the complexities of teaching electricity[10]. However, the difficulties faced by elementary school teachers when teaching electric circuits are not just caused by misconceptions or a lack of content knowledge. Elementary school students in Korea learn electric circuits mostly through experiments, and various situations can occur during experimental activities that may or may not be anticipated by the teacher, affecting the teacher’s confidence in teaching the topic. Accepting that unexpected situations are important parts of science instruction means that it is important to understand teachers’ responses to them. The quality of the teacher is the main factor that determines the quality of science lessons, particularly lessons that rely on experimental and inquiry-based activities.

Watson noted that an unexpected question asked by students might open the classroom to a new direction of learning, one less often achieved through planned teaching[11]. Unexpected situations can be an opportunity to show a powerful application of previously learned material or address a topic in a more interesting way than the teacher might have been able to think of beforehand[12]. Therefore, such a moment requires teacher expertise. The term “jazz improvisation” is used as a metaphor in mathematics education to describe the complex uncertainty in classroom situations[13]. Rowland and Zazkis analyzed how three mathematics teachers responded to an unexpected situation[14]. They described the situation as “contingent” and found that the teachers’ responses to unexpected situations created by students fall into three categories: to ignore, to acknowledge but put aside, and to acknowledge and incorporate. Moreover, it was argued that teachers’ responses to problematic contingent moments fundamentally depend on their mathematics knowledge.

Unexpected situations in the classroom are events that teachers do not plan or anticipate but that can change the direction of learning, requiring teachers to behave as experts. Few studies have been conducted on electric circuit lessons in elementary schools, especially concerning what happens in the lesson and how the teacher responds. Our aims in this study are to identify the causes of unexpected situations during elementary school electric circuit lessons, to understand how an experienced teacher responds to these situations, and to determine the factors affecting the teacher’s responses.

Thus, this study addresses the following research questions: 1) How does an experienced elementary school teacher respond to unexpected situations in electric circuit lessons? 2) Which factors affect her responses?

In this paper, we analyze and report a case study, which can be described as “a study of the particularity and complexity of a single case, coming to understand its activity within important circumstances”[15]. Because in a case study there is a close relationship between the context of the study and the findings, we now describe the context.

1. Research participant and context

This study was conducted in Korea, where the elementary school science curriculum includes four areas of physics: force and motion, electricity and magnetism, heat and energy, and waves. Elementary students have three science lessons per week[16]. Electric circuits, the topic of this study, are introduced in the “Use of Electricity” sixth-grade unit, which includes a comparison of the brightness of electric bulbs.

The participant of this case study, “Teacher A,” is an experienced elementary school teacher. She is a highly-regarded sixth-grade science subject teacher who was happy to participate in this work. Willingness is important in a case study because the participant will share beliefs, intentions, and difficulties directly related to the focus of the study. Teacher A graduated from one of the best universities of education (the typical four-year program for elementary teacher education in South Korea), and for her master’s degree, she majored in elementary science education. In her mid-40s, she has 21 years of teaching experience and has frequently taught science. She has been an instructor at an institute for gifted students in the District Office of Education, an instructor for elementary teacher training, and a writer of science teaching materials for school teachers.

Teacher A has her own methods of science teaching. She does not ask students to open textbooks except during the unit summary because she thinks that using a textbook might limit students’ thinking. Her students prepare “science notebooks” for writings and drawings to record their learning. She does not use PowerPoint, video clips, or the worksheets that most Korean elementary school teachers use in their science teaching. Instead, she prefers to ask students questions and listen to their answers.

The school where Teacher A works is a public school with a good reputation, located in an apartment-intensive area in downtown Seoul. Many of the school’s parents are professional, financially well-off, and interested in their children’s education. Students receive a variety of private tutoring after school in subjects such as maths, English, and science. For science, many students use private institutions or online courses to study the contents in advance.

When this study was conducted, in 2020, there were more online classes than face-to-face classes in the school, owing to the COVID-19 pandemic. However, the “Use of Electricity” unit was mostly taught in person from October to November. We observed one of the five class groups taught by Teacher A, taking into account the situations of Teacher A and the school for more convenient obervations. We obtained the consent of the school principal, the students, and the parents.

Since it was difficult to conduct group experiments due to the pandemic, Teacher A prepared an individual experiment kit for each student. These kits gave students more opportunities to connect electric circuits (using the given electrical components) than if they had participated in group experiments.

2. Data collection and analysis

Video recordings of classroom observations, semi-structured interviews with Teacher A (pre- and post-lesson), and field notes were used to address the research questions. We observed twelve 40-minute sessions. See Table 1 for an overview of Teacher A’s lessons in the “Use of Electricity” unit. Cameras were placed at the front and back of the classroom, and Teacher A wore a voice recorder. Video recordings and transcriptions were used as the main data source to identify unexpected situations. The researcher sat at the back of the classroom, taking field notes and recording questions that could be asked during the post-lesson interview[17].

Table 1

Content of the observed lessons.

Session	Content	Data analysis	Session	Content	Data analysis
1	Lighting up an electric bulb by connecting it to an electric circuit	◯	7	Reviewing the properties of electromagnets and how to make an electromagnet	×
2	Making an electric circuit with the given materials	◯	8	Making a toy using electric circuits	◯
3	Using different connection methods to explore their differences (Changing the brightness of the electric bulb according to the battery connection method)	◯	9	Evaluating the experiment - Building an electric circuit that results in the brightest electric bulb - Building an electric circuit that results in the darkest electric bulb	◯
4	Changing the brightness of an electric bulb according to the electric bulb connection method	◯	10	(Online lesson) Sharing ideas about how to use electricity wisely	×
5	Movement of a compass needle around a current-carrying wire	△	11	(Online lesson) Making and sharing campaign materials on how to use electricity wisely	×
6	Reviewing and summarizing the properties of electromagnets	△	12	(Online lesson) Finding out how electromagnets are used in people’s everyday lives	×

Note: ◯ = Included in data analysis; × = Not included; △ = Partly included.

The teacher interviews, which provided additional information on her thoughts and beliefs[18] about science teaching and learning, were conducted for approximately 1.5 hours before and after the classroom observations. In the pre-lesson interview, we asked Teacher A about her teaching plan in relation to the unit’s achievement criteria. We also asked her about her experiences, goals, and values related to science teaching, using these insights as basic data to understand her science lessons. After Teacher A’s lessons, the researchers viewed the video recordings, and the dialogs between Teacher A and her students during unexpected situations were transcribed to prepare semi-structured questions for the post-lesson interview. Most post-lesson interview questions dealt with unexpected situations during the lessons and investigated Teacher A’s intentions or reasons for her responses. We conducted the post-lesson interview five weeks after the pre-lesson interview. The questions included: “Why did you act like that when students asked that question?” and “Why did you use those types of analogies or explanations to help students understand?” Furthermore, after analyzing the data, we held an additional 30-minute interview with Teacher A via phone to clarify her intentions and thoughts. We asked her to explain in detail the reasons behind her response to particular situations and to check whether the analysis results were correct[19].

Data analysis began with the interactions between Teacher A and her students throughout the unexpected situations. The field notes included short explanations about the unexpected situations and were used to support the analysis. As our specific interest was in electric circuit lessons, the lessons on electromagnets (parts of sessions 5 & 6 and Session 7) and the online lessons on using electricity wisely (sessions 10–12) were excluded from the data collection and analysis. After the researchers had individually identified the unexpected situations in the lessons, the results of individual identifications were compared between researchers.

Determining what is or is not an unexpected situation is problematic. In this study, the situations that changed Teacher A’s flow of instruction (and thus, appeared to be unexpected) were taken to be unexpected situations. These included questions asked by students, unexpected experimental results, and explanations or analogies that Teacher A used to help students understand. It was agreed that there were four unexpected situations, and the related episodes were extracted from the video recordings. Thereafter, we summarized how Teacher A responded to each situation. For unexpected situations, the expressions used by students were quoted verbatim to emphasize the situation, and Teacher A’s responses were summarized by keywords that represented her words and actions. Subsequently, we identified and classified the causes of these unexpected situations to create an in-depth lesson analysis.

We associated the teacher’s beliefs about science teaching with her lessons to determine the factors affecting her responses. Teachers’ beliefs comprise their tacit assumptions about students, science learning, the classroom, and the subject being taught[20]; furthermore, their beliefs tend not to change[21]. Teachers’ teaching styles remain consistent, regardless of grade or level, and this is related to their beliefs[22]. If a teacher’s beliefs are closely related to their teaching, then we can understand Teacher A’s responses to the unexpected situations by examining the relationship between her beliefs and her teaching behavior. Thus, we extracted Teacher A’s beliefs by examining data from lesson plans, interviews, science class observations, and field notes. We revised any distorted interpretations after consulting with Teacher A. The validity and reliability of the results were ensured through the triangulation of data, Teacher A’s confirmation, and a review by colleagues who majored in science education[23].

1. Unexpected situations

We identified the unexpected situations that occurred in the electric circuit lesson and Teacher A’s responses. In the subheadings below, the phrases in quotation marks are the students’ statements that prompted unexpected situations, followed by the teacher’s responses during the lessons after the colon.

1) “The electric bulb is broken”: Electrical components are consumables/Why doesn’t it work?

Teacher A prepared kits for individual experiments in the electric circuit lesson. Each kit contained two of each of the followings: electric bulbs, electric wires, 1.5 V batteries, battery holders, and switches. Korean elementary schools commonly adopt small-group experiments and activities in science lessons to allow students to solve problems collaboratively. However, during the COVID-19 pandemic, the Ministry of Education announced guidelines that required minimized contact among students, placing restraints on educational activities that involve shared course materials[24]. Thus, Teacher A planned individual experiments, a downside of which was that she had to check nearly 30 experimental kits for missing or broken components before and after the lesson.

The following is a scene from the first Session on what constitutes an electric circuit, where the students were required to connect electrical components and turn on an electric bulb.

This situation was unexpected and troublesome because it happened more frequently than when students worked as a group. The situation arose almost in every lesson and was caused by the students or the poor quality of electrical components. These two causes could elicit unexpected situations either individually or in combination. The cases in which students were the cause can be subdivided into: (a) when students lost electrical components and (b) when students handled the tools carelessly, thereby breaking the components. For example, students may quickly and repeatedly press the switch for fun, breaking the switch’s contact. These broken components are passed on to the students in the next lesson, causing further malfunctions in the electric circuits. There are many reasons why an electric bulb does not light up even after the circuit is correctly connected, such as electrical component failure, poor connection between electrical components, or incorrect battery direction. However, if an electric bulb did not light up, some students assumed that the bulb was broken and asked to replace the bulb instead of exploring the cause of the fault. Teacher A responded to this situation as follows.

The situation above shows that the preparation and management of experimental tools affect both the experimental process and the results and that the malfunction of electrical components creates unexpected situations that can cause difficulties in teaching an electric circuit lesson. However, when we asked about the difficulties caused by the broken or missing electrical components, Teacher A answered:

Teacher A considered the electrical components used in the experiment as consumables that she could easily provide. Therefore, she did not perceive the unexpected situations arising from poor component quality or tool malfunction as difficulties; instead, she had students replace the components. Moreover, she gave students the opportunity to solve their problems themselves by asking, “Why doesn’t it work?”

2) “I connected them as shown in the textbook, but the electric bulb won’t light up”: The textbook might limit students’ thinking

Teacher A did not use a textbook during the lesson except when summarizing the unit. She always told the students to clear their desks at the start of the lesson. After removing the textbooks, Teacher A would tell the students about real-life examples of electric circuits. Subsequently, she provided experimental “missions” that students had to carry out, giving them a chance to experiment freely and individually.

An unexpected situation occurred in Session 3: “Features according to the connection method.” Teacher A set students a mission to make electric circuits with different connection methods, using two batteries and one electric bulb, and to compare the brightness of the electric bulbs. She was walking around the classroom helping the students and discovered one student who did not ask for help despite their electric bulb not lighting up. The fault in the circuit arose because the student had used one electric wire to connect to the (insulated) middle of another wire. The student had referred to the textbook to solve the mission set by Teacher A, and the textbook displayed the image shown in Fig. 1 (Left). The student had seen the electric circuit depicted in the textbook and simply followed what was shown in the image.

Figure 1. (Color online) The image of a circuit shown in the sixth-grade science textbook (Left) and an image of student-made circuit (Right).

In this situation, Teacher A explained again the concepts of conductors and non-conductors that the students had learned in Session 1 and corrected the student’s mistake.

The unexpected situation above was caused by the images in the textbook. The student connected the electric circuit (Fig. 1, Right) by just referring to the image shown in the textbook (Fig. 1, Left), which shows that the middle of the electric wire was connected without stripping. Teacher A shared her thoughts on this situation:

Teacher A could identify the difficulties faced by students during individual experiments and provide suitable guidance by explaining the roles of conductors, non-conductors, and electric wires. Regarding the unexpected situation caused by the textbook image, Teacher A explained why she makes students take out the textbook only when necessary:

3) “The electric bulb goes off when I press the switch and on when I let go”: Series or parallel?/How are the classroom lights connected?

In the pre-lesson interview, Teacher A claimed that the key learning outcome from the electric circuits’ lesson should be the connection method. Understanding the electric bulb connection method, based on the features of series or parallel circuits, should naturally lead to an understanding of how to connect the batteries. Thus, Teacher A taught concepts in a particular order (connection of electric bulbs → connection of batteries) instead of the order presented in the textbook (connection of batteries → connection of electric bulbs). Teacher A used the following analogy to help students understand the characteristics of the connection method:

Teacher A did not explain the connection of batteries first because students memorize series and parallel through the way in which the batteries are placed, such as “the series is in a row” or “the parallel is side by side.” Teacher A tried to prevent simple memorization of the connection method. However, during the lesson on the connection method, the following situation occurred:

In the situation above, the student lacked an understanding of serial and parallel connections and, thus, could not determine how to connect a new electrical component (the switch) to make the desired circuit. The switch that was connected in parallel operated in a way that was contrary to what the student knew, which confused them. In this unexpected situation related to the connection method, Teacher A reacted by giving an example of the classroom lights and light switch.

The situation above could be attributed to various causes, one of which, as noted by Teacher A, is the textbook. Specifically, the order in which it presents connection concepts (connection of batteries → connection of electric bulbs), its explanation, and the figures showing the two connection methods. In sixth-grade science, the connection of batteries is explained by the connection of poles (same or different poles) and the connection of electric bulbs by the number of electric wires (one or multiple). These concepts are shown in simple images in Figs. 2 and 3.

Figure 2. (Color online) Images in the sixth-grade science textbook explaining the serial and parallel connections of batteries.

Figure 3. (Color online) Images in the sixth-grade science textbook explaining the serial and parallel connections of electric bulbs.

The explanation in the textbook does not help students understand the connection method in terms of a closed circuit, and the accompanying figures convey the idea that series means “in a row” and parallel means “side by side.” Tsai et al. observed that students have difficulties understanding the different concepts (voltage in series, electric current in parallel) in serial and parallel connections owing to the influence of teachers who teach based on the textbook and its explanations[25]. As such, the concept presentation order, explanations, and images in textbooks may affect students’ learning of concepts.

4) “One of the electric bulbs won’t light up in serial connection”: Use of a plausible but incorrect analogy

In the experiment comparing the brightness of the electric bulbs according to the electric bulb connection method, Teacher A reviewed the characteristics of serial and parallel connections before the experiment. She then told the students to connect the batteries in series but to freely connect the electric bulbs so that there could be either one or two current-carrying wires. However, unexpectedly, when two electric bulbs were serially connected, there was a case in which one bulb lit up, but the other either did not light up or only weakly lit up. Teacher A approached the students who claimed that the electric bulb seemed to be broken, made them check whether the electric bulb was the problem, called the attention of all students, and explained as follows:

The cause of the unexpected situation above was the uneven quality of the electric bulbs, which was related to their resistance. If one of the two electric bulbs were replaced to keep the resistance consistent, it would allow both bulbs to light up; however, the teacher reference books do not provide any information about this. Teacher A also did not have relevant experience or knowledge, which led her to use an analogy in which one of the students shares a meal with his brother to explain the experimental result. The analogy she used explained the result “plausibly,” which was why student 1 seemed to understand the principle from her explanation. Analogies facilitate learning by comparing new concepts with students’ real-life experiences and visualizing abstract concepts[26]. Teacher A used “a possible experience of a student” as the analogy to explain to students what was observed in the experiment; however, she had incorrect knowledge. Student misconceptions do not easily change once formed[27], so teachers must pay attention when explaining concepts beyond the curriculum level.

5) “How do we check if the lights at home are in series or parallel?”: Explanation based on incorrect experimental result

Teacher A reviewed the content related to the electric bulb connection method at the beginning of Session 5. She reminded students of the difference in brightness between the serial and parallel electric bulb connections in the previous experiment and suggested that they bring this idea to the classroom.

In Session 3, Teacher A explained that the three rows of lights on the classroom ceiling are serially connected to a switch, and the lights in different rows are connected in parallel. She also said that the two lights in one lightbox are connected in parallel to avoid any inconvenience when one goes off. However, in Session 5, she explained the characteristics of a parallel connection in terms of the brightness of the light. Subsequently, she told the students to consider how the lights were connected in their houses.

When Teacher A emphasized the need to apply what they had learned to their real lives, one student asked how they could be sure whether the lights had a series or parallel connection, presenting an unexpected situation. The teacher responded that they could check the connection method by comparing the brightness of the lights and applying what they had learned. Although the brightness difference was due to the uneven quality of the electric bulbs (in Session 4), the teacher explained this phenomenon through a plausible analogy and then applied this analogy to the student’s question about light connections in real-life.

2. Factors affecting Teacher A’s responses to unexpected situations

Teacher A willingly replaced or provided electrical components as needed, recognizing that electrical components are consumables. She presented what she thought were the key concepts first, instead of following the order in the textbook, and limited the use of the textbook. If the students did not understand the concepts, she helped them understand by using real-life examples or analogies. However, she held incorrect knowledge of the observed phenomena, and an analogy she used to help students understand actually created an unexpected misconception.

The next section analyses why Teacher A responded to the unexpected situations during the lesson in the way she did and which factors affected her responses.

1) Emphasis on scientific inquiry experience

Teacher A let the students conduct individual experiments by providing experimental kits. She attached utmost importance to the fact that the experiment kits allowed students to explore and created an environment to promote and guide their inquiry.

Cho et al. demonstrated that teachers think that conducting exploratory activities during science lessons is difficult because of external factors, such as a lack of time, facilities, materials, and student skills[28]. This issue is mainly attributed to teachers limiting inquiry to “open inquiry” only. Open inquiry dictates that students must take the initiative, for example, coming up with questions, making plans, and collecting and interpreting data. Thus, it is often believed that inquiry-based learning can be done only by students in upper grades or those specializing in science[29]. The level or emphasis of inquiry may vary depending on the intended outcomes of the teacher[30]. Therefore, Teacher A gave students the chance to investigate electric circuits by freely touching and connecting the electrical components (without opening the textbook) to allow them to explore independently:

2) Relationship between science and real-life/student-centered lessons

Teacher A emphasized the relationships among science, real-life, and students’ experiences in the interviews:

Teacher A’s thoughts are consistent with the argument that individual student experiences must form the basis of science learning[31]. Teacher A used a possible student experience (forming a circle) as an analogy and emphasized a real-life example (the classroom light connection) in relation to the unexpected situation.

Students have difficulties linking science and science learning because they fail to perceive that science is connected to everyday life, experiences, and cultural resources[32]. Thus, many studies have emphasized the contextualized learning of physics[33, 34]. Teacher A enthusiastically used real-life examples and student experiences and wanted the students to apply what they had learned to real-life whenever they used electricity.

However, Teacher A applied a real-life example to the serial connection of bulbs (specifically the issue caused by the uneven quality of the bulbs) based on her own beliefs about the science lesson, thereby giving an incorrect explanation when a student asked how they could check the light connection method at home. According to Jeong and Park, students’ misconceptions about everyday contexts may be understood or interpreted differently from the teacher’s intention[35]. Teacher A’s case, meanwhile, shows that the incorrect understanding and interpretation of a teacher who values the use of everyday contexts in science lesson may confuse students.

3) Acquisition of scientific concepts

Although it is a common result of the experiment that when two electric bulbs are connected in series, both are dimmer than when one electric bulb is connected, Teacher A found out that the brightness of the two electric bulbs connected in series was uneven through questions from students in lesson. Below, Teacher A described why she explained the unexpected results using an analogy about sharing a meal.

Teacher A planned to teach Unit 5 (Energy and Life) after Unit 1 (Use of Electricity). Unit 5 of the curriculum states that there are various forms of energy and that these can be converted. There is no mention of energy conservation. Moreover, Teacher A’s analogy about the older and younger brother sharing a meal in one bowl may cause a misconception. Considering the direction of the current in the electric circuit (from the positive to negative poles), the electric bulb connected in front is the older brother, the electric bulb at the back is the younger brother, and the “something (food)” inside the circuit is used up consecutively. In the post-lesson interview, Teacher A referred to this “something” as “electric energy” and said she used this analogy based on the scientific knowledge that energy is conserved. During the lesson, she did not tell the students about the concept she wanted to explain or the relationship between the concept and analogy. The teacher’s analogy seemed to imply that what was used up by the electric bulb was the “electric current,” which students had already studied. The idea that the electric current is consumed in an electric bulb is a typical misconception held by students[9, 36]. Teacher A’s case shows that, although an analogy may be an effective strategy for teaching abstract concepts, it may also present unexpected difficulties if the teacher is not careful about their use.

Choi et al. reported that teachers with high PCK (pedagogical content knowledge) focus on using analogies and tend to teach concepts according to their high level of knowledge about the curriculum[37]. Thus, teachers with high PCK think that students need to learn the concept behind a phenomenon, even if that concept exceeds the level required by the curriculum. Teacher A showed similar beliefs because although she emphasized inquiry, she also believed that students must acquire the relevant scientific concepts:

Although inquiry is emphasized in science lesson, knowledge, concepts, and principles cannot be neglected, and the demands of students and parents for the learning of concepts cannot be ignored. Thus, Teacher A explained the unexpected experimental results using an analogy to make it easier for students to understand.

3. Causes of unexpected situations during the electric circuit lesson and factors affecting Teacher A’s responses

Figure 4 illustrates the unexpected situations observed in Teacher A’s electric circuit lessons and their causes, her responses to the situations, and the factors affecting these responses. The unexpected situations and the teacher’s responses extracted through classroom observation are indicated by full arrows. The causes of the unexpected situations and the factors that influenced the teacher’s responses, found via analysis, are indicated by dotted arrows.

Figure 4. Unexpected situations in the electric circuit lessons and their causes, Teacher A’s reactions to the situations, and factors affecting these reactions.

Four unexpected situations were observed. The first situation, “Frequent failures and breaking of electrical components,” occurred because of students’ neglect and/or the poor quality of experimental components. The second one, “Electric circuit that does not light up,” was caused by using the textbook. The third unexpected situation, “Error in experimental result,” was due to uneven electrical components. The last one came from “Teacher’s misinterpretation of the experimental result and her own misconception”. Teacher A responded to each situation in her own way, such as by providing new electrical components, re-explaining concepts, giving real-life examples, or using an analogy. She considered it important to provide an experience of inquiry, relate science with real-life, practice student-centered science lessons, and apply science concepts.

By analyzing how Teacher A responded to unexpected situations during lesson and the factors that affected her responses, we determined that these responses were affected by her beliefs about the kind of science lesson she intended to pursue. Pajares asserted that teachers’ pedagogical beliefs influence their classroom behavior[38]. Even though there is an ongoing debate over whether pedagogical beliefs influence actions or actions influence beliefs, much research has shown that teachers’ beliefs about teaching influence their teaching practices[39, 40].

Teacher A claimed that she wanted to practice science teaching that allowed students to construct knowledge through direct experience rather than knowledge learned from books or the internet. By analyzing Teacher A’s thoughts about science teaching and the unexpected situations that occurred in them, we confirmed that her beliefs about science teaching were related to the teaching method she used. These beliefs laid the foundation for the decisions she made (responses) regarding the various unexpected situations she faced. This finding is consistent with previous studies that have claimed that teachers’ beliefs about teaching and learning science affect their practice and actions[9,10].

This study examined the unexpected situations that occur in electric circuit lessons in elementary school science, a subject characterized by teaching and learning difficulties, and teachers’ responses to these situations. We also analyzed the factors that affect teachers’ responses. We conducted in-depth observation and analysis of the lesson of an experienced elementary school teacher who has substantial expertise in science education. We identified the unexpected situations in electric circuit lessons, the causes of these unexpected situations, the teacher’s responses to the situations, and the factors affecting her responses (Fig. 4).

The following conclusions and implications can be derived from these results. First, there are various causes of unexpected situations in electric circuit lessons. Rowland and Zazkis studied teachers’ responses to unanticipated or unplanned classroom events, usually triggered by students in the mathematics classroom[14]. Here, we found that unexpected situations could be caused not only by students but also by the experimental components, a textbook, and even a teacher’s misconception. The case of Teacher A showed that the “Use of Electricity” unit is quite difficult to teach even for an experienced teacher with a lot of science teaching familiarity. Nevertheless, guidance related to these causes is not supplied in reference books for teachers or teacher training; thus, an effective action plan is required to help teachers with electric circuit lessons by dealing with commonly occurring issues.

Second, the teacher’s responses to unexpected situations were affected by her beliefs about science teaching. The causes of unexpected situations highlighted by previous studies as difficulties in science teaching may not, in fact, represent difficulties, depending upon the beliefs of the teacher. Teacher A did not consider the situations caused by experimental tools or students as difficulties and responded to them according to her beliefs. Teacher A repeatedly used real-life examples and analogies to help students acquire scientific concepts. She also emphasized the importance of student-centered lessons and the relationship between science and real-life. The beliefs of a teacher with expertise in science instruction may enable a teacher to not consider the causes of unexpected situations as difficulties; however, she/he can still create other unintended difficulties. Therefore, even experienced teachers must be provided with re-education opportunities to reflect upon and discuss their lessons.

Third, a teacher’s science teaching activity is influenced by many factors. Schwab emphasized that teachers must continuously make various practical choices in the classroom[43]. Expertise and background knowledge are important for making judgments in these moments[44]. Our results show that teachers decide swiftly how to respond to unexpected classroom situations and that several factors impact these decisions. Since teachers’ teaching behavior is affected by various factors, it is necessary to more closely observe and analyze the factors affecting science lessons to improve teachers’ professional experience and knowledge about teaching science.

Fourth, our results highlight fundamental concerns about whether the acquisition of concepts or the provision of inquiry experiences should come first in elementary school science education. Teacher A attached importance to learning science through inquiry but did not neglect to teach accurate concepts so that she could meet the needs of students and parents and demonstrate the real-life application of what was learned. Her beliefs about science teaching, related to the acquisition of concepts, led her to explain concepts beyond the curriculum level and apply incorrect experimental results to real-life. Teacher A taught her lessons, based on her beliefs, without much difficulty, and the students participated in the lesson more enthusiastically through individual experiments than in small groups. Nonetheless, we observed an inaccurate explanation of concepts. Teacher A’s case foregrounds the dilemma about whether imparting accurate concepts or providing inquiry experience should come first in science education studies and the science lessons taught by elementary school teachers.