Ex) Article Title, Author, Keywords
Ex) Article Title, Author, Keywords
New Phys.: Sae Mulli 2024; 74: 286-298
Published online March 29, 2024 https://doi.org/10.3938/NPSM.74.286
Copyright © New Physics: Sae Mulli.
Andreas Woitzik^{1*}, Taegyoung Lee^{2*}, Nam-Hwa Kang^{2†}
^{1}Physikalisches Institut, Albert-Ludwigs-Universität Freiburg, 79104 Freiburg im Breisgau, Germany
^{2}Department of Physics Education, Korea National University of Education, Cheongju 28173, Korea
Correspondence to:^{†}nama.kang@gmail.com
∗These authors contributed equally to this work.
This is an Open Access article distributed under the terms of the Creative Commons Attribution Non-Commercial License(http://creativecommons.org/licenses/by-nc/3.0) which permits unrestricted non-commercial use, distribution, and reproduction in any medium, provided the original work is properly cited.
With increasing attention drawn towards quantum physics and its applications in teaching and research, the question of which concepts of quantum theory can be taught at different educational levels becomes more and more important. To this end, we compare the curricula of Germany (Baden-Württemberg) and South Korea. In Germany, more students take physics courses that contain quantum physics than in South Korea. We find that many quantum physics learning objectives are commonly covered, but with recent increases in quantum physics content in both countries’ curricula their approaches increasingly differ. The South Korean curriculum focuses more on technology and classical quantum concepts, whereas the German curriculum is more concerned with epistemological questions. Through an investigation of the textbooks of both regions, we found differences in laboratory activities and approaches to deal with some concepts. The findings demonstrate some consensus on the content to be taught in high school physics while the differences in the curriculum and textbooks of the two regions provide insight into pedagogical approaches and future research.
Keywords: Quantum physics, Curriculum, High school, Textbook
As curricula are shaped by the living conditions of the discipline as well as the societies in which they are anchored, they are subject to constant changes[1,2]. A field that is currently receiving growing attention in physics research and education is quantum physics. Quantum physics is not a new field, but in recent years, research efforts in quantum technology have greatly increased with initiatives like the European Quantum Flagship and interesting applications such as quantum cryptography, quantum metrology, or quantum chemistry[3-6]. This is not least evidenced by the Nobel Prize in Physics 2022, which was awarded to Alain Aspect, John Clauser, and Anton Zeilinger for fundamental work in quantum physics. Hence, it comes as no surprise that quantum physics by today is well-established in many physics curricula[7].
In this paper, we examined similarities and differences in quantum physics education of Germany and South Korea (Korea hereafter) at the upper secondary level in terms of curriculum and textbooks. Previous research on curricular comparisons mostly covers overall physics or general science curricula[8-11] while only a few recent studies examined quantum physics education at the secondary level[7]. Stadermann et al. recently compared quantum physics curricula of 15 countries, mostly in Western Europe[12]. As a result, the study provides a useful overview of the European landscape of quantum physics in upper secondary school curricula. However, their comparisons missed the curricula of Asian countries. One goal of this paper is to deliver a more in-depth comparison by focusing on two countries’ curricula, one from Germany and the other from Korea. Thus, we chose to investigate both the curricula and textbooks of the two countries. Both countries are similarly developed in means of the Human Development Index, and their economic systems rely on cutting-edge technologies often based on quantum technologies. Furthermore, both have long-established traditions in education. For comparison, we selected the secondary school physics curriculum of one German state and the Korean national curriculum. The two regions are interesting to compare since their recent curricular revision periods coincide.
As technological applications of quantum physics are widely utilized, quantum physics has gained importance in physics and engineering as well as in the educational arena[5,11]. Quantum physics is known for its difficulties due to its counterintuitive concepts, mathematics dependency, and lack of firsthand experience. Nonetheless, in many countries, basic concepts of quantum physics have been in the secondary school curriculum for many years[12,13]. A review of the research on secondary and lower undergraduate-level students' understanding of quantum physics concepts and teaching approaches showed 74 papers published over 20 years[11]. In the paper, student learning of quantum physics is categorized into four areas, i.e., wave-particle duality, wave function, atoms (e.g., energy levels), and quantum behaviors (e.g., Schrödinger equation, superposition). Among these areas, studies examined secondary school students’ learning of wave-particle duality, wave function, and atoms indicating that these topics are commonly addressed at the secondary level. The review demonstrates that students have difficulties in understanding concepts in those areas, which originate from the classical view of particles or phenomena.
Other studies have examined effective teaching strategies for quantum physics. Computer simulations, animations, and visualization are prevalent approaches tested in research, but recently experiments and demonstrations are also tested for their effectiveness[2,11,14,15]. Among these, some strategies are tested for secondary school students[3,15]. For example, in teaching wave-particle duality and the uncertainty principle, Feynman’s diagram approach (sum over paths) was tested and found to be effective for students' understanding of the concept of duality and the uncertainty principle[14].
In terms of the quantum physics curriculum for secondary schools, studies have examined the content and nature of quantum physics curricula, its manifestation in the textbook, and expert opinions on quantum physics content for secondary curricula[12,16-19]. In 2019 a large international workshop on teaching quantum physics was organized by GIREP (International Research Group on Physics Teaching), discussing curricular goals[18]. In the workshop, four curricula goals of quantum physics education at the secondary level were drawn: (1) a clear understanding of the different views between classical and quantum physics, (2) a basic understanding of the mathematical formalism in quantum physics beyond qualitative understanding, (3) a philosophical understanding of the nature of quantum physics, and (4) knowledge of modern quantum technologies and their influences on society.
A few studies examined how upper secondary school textbooks introduce quantum physics content and perspectives[17,20]. For example, Ha et al. examined how the photoelectric effect is explained across ten Korean high school physics textbooks[20]. They found that introductory physics textbooks emphasize the application of the photoelectric effect while upper-level physics textbooks highlight the principle behind it. This difference seems to be related to the national curriculum that dictates the textbooks.
In terms of epistemic perspectives underlying quantum physics in the textbook, Lautesse et al. examined how two epistemologically different perspectives were shown in French upper secondary school textbooks[17]. They identified two views on quantum objects, a “conservative” and an “innovative” view. The conservative view is characterized by the conservation of classical terms such as wave, particle, and duality to understand quantum phenomena while the innovative view argues for new terms such as quantum or quantum object to give quantum objects their own identities without resorting to classical concepts. In their analysis of five textbooks, only one textbook used conservative vocabularies exclusive to the innovative concept of quantum objects while the others mixed vocabularies of the two perspectives. Similarly, in their investigation of Korean high school physics textbooks, Cheong and Song revealed the presence of various viewpoints regarding particle-wave duality, potentially resulting in misconceptions, as indicated by the authors[21].
Collectively, a consensus appears to exist regarding the significance of incorporating quantum physics into upper secondary school curricula and the pursuit of strategies to render the subject more accessible to upper secondary school students[15,18,19]. However, there remains a need for additional research to discern the fundamental concepts of quantum physics applicable to the general public and upper secondary school students aspiring to pursue science and engineering disciplines. Moreover, an evident paucity of research exists on the pedagogical approaches employed in the classroom to teach quantum physics. Addressing this gap, the present study aims to investigate the curricular content and textbooks employed in two distinct countries as a way to glean insights into prevalent classroom teaching practices.
First, we collected curriculum documents and textbooks in each country. Since Germany is a federal state with different educational systems for each Bundesland, we collected the curriculum of Baden-Württemberg that had its last major revision of the physics curriculum in 2016 and was updated in 2022[22,23]. We chose Baden-Württemberg because its curricular revisions coincide with those of Korea. As shown in the literature, quantum physics content varies widely across German states[10]. Whenever we refer to the German curriculum, we refer to that of Baden-Württemberg. Korea adopted the national curriculum (NC-Korea) and we collected the physics curriculum revised in 2015 and 2022[24,25].
As textbooks for new curricula are not yet available, we collected textbooks that adhere to the currently taught curricula as a point of comparison. We identified three popular Korean publishers and two German publishers and collected pages of quantum physics content from their textbooks. In Germany, a single physics textbook is used for both minor and major physics courses and thus a total of 2 German textbooks were compared (textbook GA & GB). On the other hand, different textbooks are used for different courses in Korea and thus a total of 7 textbooks were compared, textbooks from three publishers for Physics I & II and one textbook for Advanced Physics (AP), which is the only one published for AP.
For our analysis, we translated all documents into English. For curriculum comparison, we divided the curriculum content using Stadermann et al.'s categories to make the results of our study comparable to those of other countries[12]. For the textbook comparison, we constructed content maps of each paragraph of texts of each textbook and then connected paragraphs to make a content flow chart. In the process, graphics and pictures are included. Once we had constructed content flow charts for each textbook, we compared them across textbooks. We grouped them into topic areas, which resulted in bigger categories than those of the curriculum comparison.
It is beyond the scope of this research to compare the influence of the differences between the educational systems in depth, so our discussion mostly focuses on the content of the curricula and textbooks. However, as background, we briefly describe an overview of the formal educational conditions, and then, we sort the contents according to similarities and differences.
The general organization of the school systems in Korea and Germany is in some respects comparable and in others rather different. Korea has six years of primary school, whereas most of the German federal countries have four years of primary school. Thereafter, in Germany mostly a tripartite secondary school system follows (8 years of Gymnasium [academic track], 6 years of Realschule [intermediate track], or 5 years of Hauptschule [vocational track]). In Korea, six years of secondary schools are comprehensive, and specializations take place within the comprehensive schools. We focus in our analysis on the German Gymnasium and upper secondary schools of Korea that are designed to prepare students for higher education in academia because quantum physics is mainly taught in these schools and lectures.
In 2021, roughly 16% of the students who were in Gymnasium took physics as a major (five 45-minute periods per week over the last two years of secondary school) and 29% as a minor (three 45-minute periods per week over the last two years of secondary school)^{1}. In Korea, in 2020, roughly 25% of the 11th graders took the first elective course in physics (Physics I, four 50-minute periods per week over 17 weeks). This number reduces to 13% of 11th or 12th graders taking the second elective course in physics (Physics II, four 50-minute periods over 17 weeks). The exact percentage of students who enrolled in the Advanced Physics course lacks official documentation, yet it is widely recognized as an uncommon choice, given its exclusion from the college entrance examination.
The number of courses and the amount of class time on quantum physics content are also needed to compare the curricula. In the 2022 revised curriculum of Korea, three elective courses, each of which is designed as three 50 minute-periods per week over 16 weeks, cover quantum physics content: (1) Physics, (2) Electromagnetism & Quantum (EMQ), and (3) Advanced Physics (AP). Physics is supposed to be taken before EMQ and AP[25]. In the German curriculum (i.e. Baden-Württemberg’s), physics is instituted as an elective taught in Gymnasium over two years. For the minor, the school or the respective teacher can choose between two options, an astrophysics focus or a quantum physics focus. Both courses cover quantum physics, but the latter covers more than the former. When referring to the minor course in this paper, we primarily refer to the one with quantum physics as the focus area.
Given the course hours and amount of course content described in the curriculum, we approximated how much class time would be spent on quantum physics content. In the German curriculum, quantum physics would take 38 hours for majors and 23 hours for minors. In the Korean 2022 revised curriculum, quantum physics content would take 9 hours in the physics course, 19 hours in the EMQ course, and 7 hours in the AP course. Taking all elective courses takes up to 35 hours. Thus, when taking all physics electives, the total hours of learning quantum physics are comparable to those of major electives in the German Gymnasium curriculum. Given the fact that AP is rarely taken by students, the typical lesson hours taken by those who are interested in physics in Korean high schools is 26, which is a little more than German physics minors. Nevertheless, it is important to note that the actual time on quantum physics content depends on teachers’ implementation.
Based on 2022 revisions, the quantum physics (QP) topics covered in Korean and German upper secondary school curricula are shown in Table 1.
Table 1 Quantum physics content topics (O: present, –: not present, N: newly adopted in the recent revision, *German astrophysics focus minor).
QP topic | Germany | Korea | |||
---|---|---|---|---|---|
Minor | Major | Physics | EMQ | AP | |
1. Blackbody radiation | – | – | – | – | N |
2. Bohr atomic model | N* | N | O | N | O |
3. Discrete energy levels in atoms (line spectra) | N* | N | O | – | O |
4. Interactions between light and matter | O* | O | – | O | N |
5. Wave-particle duality and/or complementarity | O | O | O | N | O |
6. Matter waves, quantitative (de Broglie wavelength) | O* | O | – | O | O |
7. Technological applications | – | – | O | O | O |
8. Heisenberg’s uncertainty principle | – | O | – | O | O |
9. Probabilistic or statistical nature | O | O | – | O | – |
10. Philosophical consequences | N | N | – | – | – |
11. One-dimensional model or potential well | – | N | – | – | O |
12. Tunneling | – | – | – | N | – |
13. Atomic orbital model | N | N | – | – | – |
14. Pauli exclusion principle | – | N | – | – | – |
15. Entanglement | N | N | – | – | – |
16. Schrödinger equation | – | – | – | – | N |
17. Calculations of detection probability | – | – | – | – | – |
Total (newly added) | 9(5) | 12(7) | 4 | 8(3) | 10(3) |
Enrolling in complete physics courses would grant students exposure to 12 topics in both regions. Conversely, if students opt for a minimal physics curriculum, German students, through an astrophysics focus course, would encounter 4 topics, while Korean students, engaging in regular physics, would also experience 4 topics. Despite the numerical parity, the former group would gain broader conceptual exposure, while the latter group would acquire more knowledge of practical applications.
In terms of topic coverage, both the Korean and German curricula cover eight topics of the list, whereas one topic, the calculations of detection probability is not covered in either region. 4 different topics are covered only in one of the regions. In the Korean curriculum, blackbody radiation, technological applications, tunneling, and the Schrödinger equation are covered while in the German curriculum, philosophical consequences, the atomic orbital model, Pauli’s exclusion principle, and entanglement are covered.
The Korean curriculum focuses on technological applications whereas the German curriculum focuses on philosophical discussion and answering fundamental questions. For example, for the common topic of duality (complementarity), the curricular descriptions of the two regions show such a difference.
Students can describe similarities and differences in the behavior of classical waves, classical particles, and quantum objects at the double slit. (German curriculum[23], p.31]
[12 Physics 03-03] Students can explain that the duality of light and matter is used in various fields such as electron microscopy and image information storage. (Korean curriculum[25], p.112]
In the description, the Korean curriculum includes technological applications as content goals, which are not shown in the German curriculum. On the other hand, the Korean curriculum does not include a comparison between classical and quantum physics leaving out the philosophical shift from classical to quantum physics. In presenting the unit entitled, “Quantum Physics and Matter” the German curriculum emphasizes changing viewpoints.
Students recognize that any classical model concept fails to describe the behavior of quantum objects .... they find that quantum physical findings and experiments question familiar concepts and terms (determinism, causality, orbital concepts). (German curriculum[23], p.46)
In contrast, the Korean curriculum introduces the quantum physics unit in the following way showing its emphasis on technological applications:
In the realm of the quantum and microscopic world, students can appreciate the unique characteristics and strange and beautiful behavior of the microscopic world...and have an opportunity to explore the impact of precision science dealing with the sub-atomic level on the development of modern civilization and technology. (Korean curriculum[25], p.17)
We identified topics that were newly included in the curricular revision in 2022. The first observation is that no quantum physics topics were dropped from the previous versions of the curricula while many new ones were added. Before the recent changes, the list of topics covered by the curricula was very similar between the two countries covering four to seven topics (Table 1). This hints at a consensus on the importance of quantum physics in the physics education landscape[3,4,5,6].
Given the common increase in the QP content, however, the German curriculum added more topics to courses (12 in total) than the Korean curriculum (6 in total). Most of the new topics in the German curriculum are in alignment with the literature that asks for addressing philosophical perspectives and concepts related to recent quantum technologies such as the Pauli exclusion principle and entanglement[12,17,18,19,26]. On the other hand, the new topics added to the Korean Curriculum include a historical topic (Blackbody radiation) and a repetition of existing topics from the prior course to the next course in the sequence (from physics to EMQ or from EMQ to HP) to address them in-depth. An exception to this includes the topic of tunneling, which is to add a technological application to address: “[12EQ03-03] Students can explain the tunnel effect and investigate and present related phenomena and technologies.” (Korean curriculum, EMQ[25], p.176)
Thus, the directions of expansion of the quantum physics curriculum diverge. The German curriculum extends to the topics of the so-called “second quantum revolution” while the Korean curriculum deepens existing content.
Overall, German textbooks differ from each other more than Korean ones. This can be attributed to the different educational governance. In Germany, each state has its own curriculum, and thus many German textbooks are written to be applicable to multiple states, resulting in variations depending on the state curricula they cover. In contrast, in Korea, textbooks are approved by the government based on their fidelity to the national curriculum, which leads to a relatively uniform nature. Nevertheless, textbooks shed light on how quantum physics is taught in the classroom[27].
When it comes to the volume of textbooks covering quantum physics content, the two regions demonstrate comparable results. In the German case, the ratio of pages that cover quantum physics content is 14–15% for both textbooks, which is not much different from the overall ratio found in Korean textbooks. In the Korean case, for Physics I textbooks, the ratio ranges from 16% to 17%, for Physics II between 8% and 9%, and for AP the ratio is 16%.
We found that German textbooks covered topics additional to the curriculum content, and thus topics such as the Schrödinger equation, tunneling, laser, and other technological applications were covered in the textbooks we analyzed. This could be due to the fact that the German textbooks cover the curricula of multiple states and the role of curriculum as dictating the minimum not the maximum of the textbook content.
Due to the interconnectedness of various topics within written texts, the content of the textbook was classified into five topic areas broader than the topic categories used for the curriculum comparison: (1) atomic energy levels, (2) duality and complementarity, (3) uncertainty principle, (4) probabilistic character and tunneling, and (5) entanglement. For the sake of comparison, topic areas commonly addressed up to the most coverage (AP in Korea, major in Germany) were compared except for the entanglement that was covered only in German textbooks.
Atomic energy levels. This topic area covers two topic categories of the curriculum comparison: ‘Bohr’s atomic model’ and ‘discrete energy levels in atoms (line spectra)’. Regarding this area, textbooks of both regions cover similar content. All the textbooks address the Planck constant, energy quantization, Bohr’s atomic model through hydrogen atoms, and discrete energy levels through line spectra. They all include calculations of photon energy (
In all textbooks of both regions, Bohr’s atomic model is described but some introduce it in passing while others elaborate it to discuss the history and/or to relate it to discrete energy levels and line spectra of hydrogen atoms.
Given the similarity of the content, some differences were found. All Korean physics textbooks introduce the topic with the spectrum that students are familiar with from middle school science class while the AP textbook introduces it with Bohr’s atomic model which is also what students are familiar with. On the other hand, both German textbooks start the topic with the quantized energy of photons, introducing the photoelectric effect and the Franck-Hertz experiment. This is because the topic is addressed after a chapter on photons. In other words, the German textbooks have a chapter on photons prior to atomic energy levels, and they are logically related in the written explanations. The Korean AP textbook also explains the nature of photons prior to energy levels, but it is treated as a separate topic. Furthermore, the Franck–Hertz experiment, the first measurement to show the quantum nature of atoms is not in Korean textbooks.
Concerning the spectral lines of the hydrogen atom, German textbooks introduce the Schrödinger equation and the model of the one-dimensional potential well. In Korean textbooks, the Schrödinger equation and the potential well model are addressed only in the AP course that students rarely take.
Another difference is how applications are presented. The German textbooks introduce many applications including X-rays and fluorescent and LED lamps in relation to quantum concepts. On the other hand, only one of the Korean textbooks introduces a fluorescent lamp as an application related to the quantum concept. Interestingly, the Korean AP textbook introduces X-ray in a unit on technological applications, as a type of electromagnetic wave, not related to the quantum physics concept of photon. Similarly, LED is introduced but it is in the chapter on optics, and quantum nature is not related.
Overall, it is evident that the content encompassing atomic energy levels is similar across textbooks from both regions. However, a discernible distinction arises in the pedagogical approach employed to present the subject matter. Notably, German textbooks have a greater proportion of empirical substantiation by various experimental results and practical applications connected to quantum concepts in contrast to their Korean counterparts.
Duality and/or Complementarity. This topic area covers three topic categories of the curriculum comparison: ‘Interactions between light and matter’, ‘wave-particle duality and/ or complementarity’, and ‘matter waves, quantitative (de Broglie wavelength)’. Experiments like the photoelectric effect and de Broglie’s matter waves are introduced in all textbooks.
Given the seemingly common content, however, there is a stark difference in the perspective on quantum objects[17]. In Korean textbooks, light and matter are described in terms of exhibiting both particle-like and wave-like behavior. Thus, both light and matter are recognized to show duality, which is substantiated by the photoelectric effect and the electron microscope.
In contrast, in German textbooks, the term ‘duality (Dualität)” is not used to describe the properties of light and electrons. Instead, the term ‘quantum objects’ is used with a definition, “Quantum objects are objects that show particle or wave properties, depending on the experiment” (GA, p.280); “quantum objects do not behave like waves and they do not behave like particles” (GB, p.301). Then, the double-slit experiment and electron diffraction are used to show that quantum objects are neither particles nor waves. Quantum objects are distanced from classical particles or waves. Instead, the term complementarity is used to describe the properties of quantum objects: “Students can (4) describe, using the example of the double-slit experiment, that although quantum objects always have wave and particle properties, these cannot be observed independently of one another. Students can explain this using the interference capability and the which-way information for individual quantum objects (complementarity)” (German curriculum[22], p.31). A Korean textbook introduces complementarity, but it is not related to duality or the nature of quantum objects.
Another notable difference of German textbooks from Korean textbooks is that many experiments are introduced in detail. For example, textbooks from both regions introduce the de Broglie wave and provide Davisson–Germmer’s experiment as proof of de Broglie’s hypothesis. Korean textbooks present the experiment as a part of history while German textbooks explain the experiments in detail. In doing so, German textbooks made the topic a process of debate and proof whereas Korean textbooks treat it as events that occurred in history as if they are completed.
Overall, it is evident that Korean textbooks stay in the historically earlier version of quantum physics concepts while German textbooks as well as the curriculum are in alignment with the recent call for abolishing classical analogies and giving quantum objects their own identities[17,21]. Furthermore, by presenting experiments in detail, German textbooks made related concepts as a process of construction, unlike Korean textbooks that made the concepts as completed in history.
Uncertainty principle. Heisenberg’s uncertainty principle is present in all of the textbooks analyzed in this comparison. For the two German textbooks, the presentation is similar in content and length. Both textbooks spend one chapter on the uncertainty principle, and they introduce interferometers and the concept of complementarity (using which-path information). Also, both explain why uncertainty in the microscopic world is not shown in everyday or classical physics. Among the two, only one (GA) introduces the time-energy uncertainty whereas the other (GB) provides various polarizations as examples. Another difference is how they introduce the uncertainty principle. One (GA) draws it from a mathematical argument while the other introduces mathematical expression with descriptive explanations. Regardless, they both have an exercise to apply the formula to calculate some quantities.
Korean textbooks for Physics II and AP also devote a chapter on the uncertainty principle. Interestingly, each type of textbook shared similarities with each of the two different German textbooks respectively. AP textbook uses a mathematical argument to introduce uncertainty principle while Physics II textbooks present only the mathematical expression of position-momentum uncertainty with descriptive explanations. Nevertheless, all of them have an exercise of calculating some quantities using the equation just like German textbooks. Also, both types relate the uncertainty principle to complementarity just like German textbooks. Similarly, one type (AP) has the time-energy uncertainty while the others (Physics II) do not have it.
The uncertainty principle part is where Korean textbooks explicitly address differences between classical and quantum physics. This principle is subsequently applied to an introduction to the modern atomic model (orbital model) by explaining failure of Bohr’s orbit model.
Overall, this topic area showed the most similarity between Korean and German textbooks in terms of content and approaches to addressing the topic.
Probabilistic Characteristics and Tunneling. This topic area covers five topic categories of the curriculum comparison: ‘probabilistic or statistical nature’, ‘philosophical consequences’. ‘one-dimensional model or potential well’, ‘tunneling’, and ‘Schrödinger equation’. Not all textbooks address all of these topics, and emphasis vary across textbooks.
The probabilistic nature of quantum physics is stressed strongly in German textbooks. It is early on discussed in the textbooks in its own chapters or subchapters. Interference of matter as well as light at the double slit is discussed and a stochastic interpretation is given. For example, in GB probability densities in position space are introduced and plotted for slit experiments. GB also discusses the concepts of causality and randomness in quantum physics. Only GA introduces the tunnel effect and relates it to a scanning tunneling microscope as an application. In all these discussions, both books repeatedly address differences between classical and quantum objects, which lead to philosophical consequences.
Korean textbooks also devote a chapter to the probabilistic nature of quantum physics usually along the atomic orbital model. All Korean textbooks introduce the Schrödinger equation along with the electron cloud model and quantum numbers. Among them, one (KA) compares the classical Bohr model with the probabilistic modern model and introduces the Bohr-Einstein debate. Another of the three (KB) introduces the tunnel effect. AP covers the Schrödinger equation, one-dimensional infinite potential well, tunneling, and the scanning tunneling microscope. Philosophical consequences are rarely addressed in any of the Korean textbooks including the one for AP.
Entanglement. As described in Table 2, the concept of entanglement was added to the curriculum in Germany (Baden-Württemberg) in 2022 while it was added to the German federal standards in 2020. Further, it is not part of the Korean curriculum. Therefore, it is not surprising that entanglement is not presented in any of the Korean textbooks that we investigated. Interestingly, although the German textbooks were designed for the old curricula that did not cover entanglement, they both cover the topic. This might be because German textbooks cover curricula of many states, some of which have adopted entanglement already[12].
Table 2 Quantum physics related student lab activities (*Similar experiments between the two regions).
German textbooks | Korean textbooks |
---|---|
GA | Physics I (Combination of all three publishers) |
(GA1) Electron interference at a graphite powder layer *(GA2) Determination of Planck constant h with LEDs of various colors (GA3) Observations of the spectrum of excited gas atoms *(GA4) Observations of the spectrum of sunlight (GA5) Investigation of a sodium flame (GA6) Investigation of X-ray spectra for exploring atomic structures | *(K11) Observation of spectra of various light sources (K12) Photoelectric effect using various light sources (qualitative) (K13) Double-slit experiments (qualitative): Comparing results from sand with those from laser |
GB | Physics II (Combination of all three publishers) |
*(GB1) Determination of Planck constant h with LEDs of various colors (GB2) Interferometer experiment for which-path-information | (K21) Comparing electric currents produced by various light sources *(K22) Determination of Planck constant h with LEDs of various colors (K23) Double-slit experiment (quantitative) (K23-1) Double-slit experiments (qualitative): comparing results from sugar with those from laser (K24) Photoelectric effect using solar cells (quantitative) |
We find distinct differences in how entanglement is presented in the two textbooks analyzed. GA introduces entanglement briefly from an introduction to Wheeler’s proposal for a delayed-choice experiment. While the thought experiment made the content mythical, the section briefly mentions future technological applications on the side, including quantum cryptography and quantum computers. On the other hand, GB extensively addresses entanglement using a delayed-choice quantum eraser experiment, a real experiment performed incorporating concepts in Wheeler's delayed-choice experiment. It is introduced by the description of entangled polarization degrees of freedom of a pair of photons, then the differences between classical and quantum correlations are discussed and thereafter quantum encryption for secure communication is detailed. Overall, the tone of GA regarding entanglement is mysterious and futuristic while the tone of GB is just like the other content that provides explanations of already accepted and applied content.
Lab activities for students. As alluded to in the literature review, simulations, demonstrations, and experiments have been devised to make quantum physics accessible to high school students[1,13]. Although textbooks are not the only source of laboratory activities for teachers and students, they are probably the main source. Thus, it is worth comparing the kinds of student lab activities presented in textbooks. In this analysis, we restrict our comparison to the textbooks sampled for this paper. Regardless, the results shed light on the range of lab activities available through textbooks as well as the differences between the two regions. On a side note, there was no student lab activity presented in the AP textbook of Korea.
The lab activities listed in Table 2 are those each textbook indicates as student experiments under various titles such as ‘experiment’, ‘attempt’, ‘exploration’, and ‘observation’. We have excluded activities where students are given data or results of experiments and asked to interpret them. For example, photos of electron diffraction are given to students to ask for an explanation as proof of the wave character of matter is not counted as a student lab activity.
As for the number of experiments, the textbooks demonstrate the same difference within a region. For example, one German textbook (GA) has many lab activities for students to perform while the other (GB) has only two. Similarly, one Korean textbook has one lab activity for each subject, Physics I and Physics II, resulting in two lab activities in total, whereas the others have two or three lab activities for each subject, resulting in four or five lab activities in total.
Two lab activities are found to be similar between the two regions: GA2 & GB1–K22, and GA4–K11 (Table 2). These similar experiments demonstrate different nuances of textbook lab activities.
Table 3 shows the same student lab activities described in one of the German and the Korean textbooks (determining Planck constant), which has the same experimental setup as well as analysis procedures, i.e., a table of data for calculating the energy of various LEDs and a graph to identify h by its slope (
Table 3 Comparison of textbook lab activities between the two regions.
(GA2) Determination of Planck constant h with LEDs of various colors | (K22) Determination of Planck constant h with LEDs of various colors |
---|---|
Task: The equation of E=hf has to be checked using LEDs. Materials… Planning… Implementation… Evaluation (Table includes voltage and wavelength for each color of LED. Colors used are red, yellow, green, blue, and UV.) Sample diagram (Energy-frequency graph) | Goal: Be able to determine h using LEDs. Materials… Procedures…. Results…. (Table includes frequency, voltage, energy for each color of LED. Colors used are red, yellow, green, and blue.) Conclusion (Energy-frequency graph) |
One experiment of GB, ‘Interferometer experiment for which-path information’ is worth mentioning. It is related to entanglement and has an activity that is widely introduced in textbooks about quantum computing[28]. This experiment is near the end of the subchapter, ‘The principle of complementarity’, which has a section on entanglement.
Figure 1(b) shows the lab setup in which the laser, a polarization filter, a double slit with two rotatable polarization filters on the slits, and screen are set from the left to the right. Students are asked to predict what will happen in the screen when the rotatable polarization filters directed differently such as ±45^{∘} from the input polarization filter and individual photons go through the filters and slits (Fig. 1(a)). Students are also asked to make a hypothesis for each angle (0^{∘}, 45^{∘}, 90^{∘}) when individual photons pass the double slit using the complementarity principle and test the hypothesis. Through this experiment, students are expected to apply what they have learned about the Mach-Zehnder interferometer with polarization filter, complementarity principle, and entangled photons in an idealized interferometer.
Quantum physics and technology. Since the treatment of technological applications was a striking difference in the e curricula of the two countries, we address how the curricular differences manifested in textbooks. Since many applications are presented in all textbooks, we discuss them through examples. Although the German curriculum does not explicitly mention technologies based on quantum phenomena, the textbooks usually cover a variety of technologies. They range from the acceleration of satellites using the momentum of photons to the fluorescence of banknotes to X-rays in medicine. Interestingly, the laser as well as LEDs and their applications are covered by their own chapters in detail in GA, but both are only used for experiments in GB and not discussed on a theoretical level.
Meanwhile, in the Korean context, technological applications are emphasized in textbooks just like in the curriculum. Achievement standards include technological applications and course goals and the teaching and learning guideline mention it. In particular, the curriculum for Physics I specified two technical applications that need to be introduced as a way to apply what they have learned: digital imaging (charge-coupled device) and electron microscope. In addition, all Physics I textbooks introduce other applications including the Hubble telescope, automatic streetlight flashers, solar-powered cars, night vision devices, and 3D scanners. This emphasis on technological applications is not shown in Physics II which is designed for science and engineering-bound students. However, AP has a separate section on advanced technology that introduces the scanning tunneling microscope, diodes, lasers, and carbon nanotubes & graphene. All these applications are mentioned in the Korean curriculum.
Taken together, both German and Korean textbooks introduce various advanced technological applications related to quantum physics. Korean textbooks tend to follow the national curriculum while basic-level physics textbooks utilize additional technological applications that seem to be intended to motivate students. Despite the lack of curricular emphasis on technological applications, German textbooks present various technological applications that not only include applications in use but also future development such as quantum computing discussed in the section on entanglement.
In this paper, we compared the quantum physics contents of curricula and textbooks in Korea and Germany as well as school contexts as boundary conditions. We find that fewer students in Korea (25%) take elective physics courses than in Germany (45%). The structure of the courses differs. In Germany, physics is designed as one subject for the last two years of high school while students might take it as a minor or major, which differs in the amount of content and class hours. Students who take physics as a major can take the physics graduation exam. On the other hand, in Korea, physics is designed as four subjects taken in sequence over a semester respectively during three years of high school. Students may take from none to all four depending on their aspired careers or college planning. Students may or may not take physics matriculation exam.
The proportion of quantum physics in the total physics curriculum is similar in both regions. Both curricula cover 12 topics while 8 of them are common. Furthermore, three core topics such as wave-particle duality and complementarity are covered by basic courses of each region (physics minor and Physics I) and also many other curricula worldwide[12]. These topics are also considered important by educational researchers[14]. Thus, there seems to be a consensus on what counts basic in quantum physics[12,13,16,17,18,19]
Given the similarity in core topics for the basic level, the greater the number of courses taken, the more pronounced the distinction becomes between the two regions. In general, the 2015 and 2016 curricula of Korea and Germany respectively largely intersect. However, interestingly the new updates of the curricula in 2022 show two different paths, especially for the advanced courses. We found that Korea focuses not only on technology with concepts but also adds historical quantum physics content to the curriculum like blackbody radiation and tunneling. Presumably, concepts are addressed in the classical areas while recent developments are emphasized through the current technical advances. These characteristics became even more apparent in the textbook analysis.
Germany on the other hand takes a more recent didactical approach covering topics like entanglement, locality, and realism. This has been regularly suggested for teaching quantum physics in German secondary schools in the last few decades[15,16].
Given the new curricula in both regions, further research on how the new curricula are implemented in practice and what learning experiences are available to students is necessary. In particular, comparative studies about the impact of the two different directions of new curricula of the two regions would shed light on the future development of quantum physics education for high schools.
The results of the textbook analysis demonstrate differences as much as those of the curricula in that some contents are almost the same while the others showed stark divergence. Korean textbooks tend to keep fidelity to the national curriculum while German textbooks deviate from the regional curriculum by covering more than the curricular content. This might be due to the different educational systems, one adopts the national curriculum while the other adopts the local curriculum under federal guidance. Research on the degree of using textbooks in the classroom and instructional practices employed within the classroom would shed light on the extent to which the curriculum and textbooks influence student learning.
What can each country learn from this study? The inclusion of entanglement and philosophical perspectives in the German curriculum and textbooks asks Korean physics educators to reflect on the content of quantum physics for high schools in Korea. As alluded to earlier, the new physics curriculum of Korea emphasizes conceptual learning primarily focusing on concepts developed before the second quantum revolution. The first quantum revolution led to inventions such as the laser and transistor in which rules of quantum physics applied, whereas the second revolution focuses on the use or manipulation of single quanta in order to exploit quantum correlations (e.g. entanglement) for technological applications in quantum cryptography, quantum metrology or possibly quantum computing. In addition to already established concepts and technologies, the Korean curriculum might need to incorporate recent development in quantum physics that is geared toward the near future.
The emphasis on technology related to quantum physics concepts in the Korean curriculum is noteworthy. It relates abstract learning to concrete substances, which would help students relate to physics better. However, the emphasis on classical quantum concepts may limit the range of technology introduced in the textbooks.
In terms of student lab activities, Korea and Germany can learn from the differences across textbooks. Lab activities of some textbooks are open-ended so that students can perform without knowing the results. This might be an effective strategy for motivating students. On the other hand, the elaboration of lab design presented in a German textbook would make students perform lab activities with minds on. Also, the lab that asks students to make a hypothesis and test it is a pedagogically effective method for engaging students[29]. Thus, this kind of lab activities should be incorporated more in textbooks.
Taken together, this study demonstrates some consensus on the content to be taught in high school physics while the differences in the curriculum and textbooks of the two regions provide insight into pedagogical approaches and future research.
For both major and minor, one subject, Physics is provided, while the curriculum is described for minors (basic with quantum focus and basic with astrophysics focus) and majors.