Lights, flames, action! – What we really learn from a chemical Christmas lecture

1 Introduction

A while ago, I was invited to present a chemistry lecture with demonstration experiments for school students during a science congress. The session featured a range of chemical demonstrations, including striking reactions with carbon dioxide. In the afternoon, the students were asked what they had learned in the individual sessions throughout the day. One student enthusiastically recalled “the Coke and Mentos experiment.” I was taken aback: I had only mentioned this experiment in passing but had not performed it. This moment prompted a deeper reflection: What do audiences actually retain from science shows? Do they remember what was actually shown, or what they expected to see?

Science shows, including Christmas lectures, represent a time-honored and widely popular format of science communication, with a tradition that dates back to 1825 when Michael Faraday first delivered a chemistry lecture intended for young people and the public. ¹ Notable among these lectures was “The History of a Candle”, which was later published as a book, laying the foundation for the Royal Institution’s annual Christmas lectures. ² Beyond that, Faraday focused on communicating science to the general public ³ and these lectures are often regarded as the inception of science communication. ⁴ Until today such lectures are a traditional part of the pre-christmas season at many universities. Yet despite their long-standing tradition and wide appeal, there is surprisingly little empirical research on their educational impact.

The first question addresses a known but under-researched phenomenon: Science shows often leave a vivid impression, but it remains unclear which ideas, concepts, or messages actually stay with the audience. Evaluating such impact poses a methodological challenge. Large-scale tools are difficult to implement in festive, informal contexts. Audience members typically leave the venue right after the show, and participation in surveys is low.

The second question focuses on the active role of students, which is still relatively uncommon in the context of university science shows. In the case presented here, a group of student teachers planned, developed, and performed a full-scale chemistry show as part of a teaching practicum. Their involvement extended from experiment selection and safety assessments to stage presentation and audience interaction. This constellation raises an important question: can the students involved gain authentic, meaningful learning experiences? Exploring this dimension contributes not only to the understanding of science shows as a communication format, but also to the development of practice-oriented teacher education.

2 Theoretical framework

Science shows, including chemical Christmas lectures, represent a distinctive form of science communication situated at the interface of education and entertainment. Their appeal lies largely in the use of live demonstration experiments, which have a long tradition in science education for engaging audiences and making abstract processes tangible. Yet, despite their popularity, the question of what participants, whether audience members or performers, learn from such events remains open. Previous research offers valuable insights but also reveals gaps: the effectiveness of demonstration-based learning is contested, the educational value of science shows as a specific communication format is underexplored, and the potential benefits for those who design and deliver them are rarely addressed.

3 Research focus

Guided by the gaps identified above, this study focuses on two complementary questions:

1. What three key insights, impressions, or contents do visitors express directly after the event?

2. What personal insights, experiences and learnings do students express after their active participation in a chemical Christmas show?

These questions allow us to investigate not only the immediate, self-reported impact of a science show on its audience, but also the potential of the format as a practice-oriented learning environment for future chemistry teachers.

4 Conception of the Chemical Christmas Show

The Chemical Christmas Lecture at the University of Graz has a long tradition. After a break of several years it has been offered again for the last five years. For the past four years, the event has been presented by students as part of a laboratory course and is thus integrated into the chemistry teaching program. The students select, prepare and perform experiments, often in the form of short sketches. Three years ago, the Christmas Lecture was renamed the Chemical Christmas Show and moved to public theaters in the city, and for the last two years it has been held in the local theatre “Schauspielhaus Graz” in front of 520 spectators. The relocation of the event to well-established cultural venues underscores the significance of the occasion and facilitates its appeal to a more extensive and heterogeneous audience Figure 1.

Figure 1:

Stage and view into the theater before the show

The study took place as part of the 2024 Chemical Christmas Show themed “Chemical Moments”. This show featured and explained popular experiments from social media, including well-known experiments such as “elephant toothpaste” and “the chemical traffic light,” as well as more novel experiments, such as the production of rubies in a microwave (see Table 1).

In preparing the experiments, special attention was given to ensuring that they were appropriate for the target audience. Emphasis was also placed on the safe execution of the experiments on stage, including a thorough risk assessment. Some of the experiments were accompanied by quiz questions about the experiment, which the audience could answer via Mentimeter. This interactive element was deliberately implemented to encourage active participation and cognitive engagement, in line with research showing that such involvement can enhance learning gains compared to passive observation. The winners were awarded prizes at the end of the show. The students presented their experiments in the form of entertaining and individually designed contributions to the show (see Figure 2).

Figure 2:

Show experiments were presented, some of which could also be imitated. Here you can see the burning banknote using 60 % rum. (Copyright: Angele/University of Graz).

At the beginning of each presentation, the underlying social media post was also presented. Only realistic experiments were considered for the show. So called fake experiments were excluded.

5 Methods

Surveying the audience after the show is challenging. To keep it as efficient as possible, the survey was limited to a single open-ended question: ‘What three things did you take away from today’s show?’ Responses were recorded using audio recorders, and no other personal data was collected. Thirty-three individuals participated in the survey. Subsequently, the students’ learnings were surveyed one week after the chemical Christmas show. All students who had been actively involved in the design and implementation of the show were surveyed with the open-ended question “What personal insights and experiences will you take away from your active participation in the Christmas show?”. Unlike the audience, the students answered the question in writing with optional using bullet points. Their responses were not recorded in interviews, as this would have required them to forfeit their anonymity. I also hoped that this approach would encourage more open and honest answers. In contrast to the audience survey, there was no limit to the number of aspects they could mention.

The responses from both surveys were transcribed and analyzed separately as part of a qualitative content analysis according to Kuckartz. ³⁰ Categories were derived inductively from the material. These categories were then grouped into subcategories where it made sense in terms of content.

Subsequently, the experiments cited in the audience survey were assigned to the show schedule. It was also evaluated whether the experiments were merely mentioned or described, or if they were connected to additional explanations from the show. These responses were then assessed for accuracy.

6 Results

The results are presented in two parts, corresponding to the study’s dual focus. First, we examine the audience’s immediate takeaways from the show, analyzing both the content and nature of their responses. Second, we explore the learning experiences reported by student presenters, revealing a distinct set of professional and personal development outcomes.

7 Discussion and outlook

Like a bit to be expected, the results indicate that the primary value of such events lies less in the direct transfer of deeper knowledge and more in their entertainment factor and their ability to enhance the public perception of chemistry. Experiments with striking visual effects like the “elephant toothpaste” or experiments with black powder left a particularly strong impression on participants and were frequently mentioned. However, these experiments were often recalled without further details or even false explanations, indicating that science shows primarily serve to spark excitement and curiosity rather than to convey in-depth scientific knowledge. Experiments accompanied by quiz questions seemed to be not recalled more frequently than other experiments. Notably, one quiz question about “glowing banana” was explicitly mentioned in audience responses, suggesting that targeted investigation of such interactive elements could be worthwhile. This aspect should be examined more specifically in future studies. Furthermore, several participants expressed enjoyment at seeing familiar experiments again, which were also among the most frequently mentioned, such as the “elephant toothpaste” or black powder. These instances may tap into prior knowledge, potentially prompting more focused observation. However, it is important to note that these experiments were often listed without any accompanying explanation, meaning no inference about improved understanding can be made in this context. Future investigations should place greater emphasis on this aspect. One possible approach is the use of test classes, which will be implemented for the next Christmas show. This will allow for more detailed feedback and make it possible to assess prior knowledge and expectations.

These findings are consistent with previous research by Sadler. ¹⁹ While such events may not always facilitate deep learning, they appear to foster positive attitudes toward science and can also contribute to a positive image of the hosting institution and its scientists. Interestingly, this effect appears to extend to the perception of research itself, as some respondents stated after the show that they believed the university had excellent scientists and high-quality courses, drawing broader conclusions about the institution’s research from the show. This is an interesting approach for further research and demonstrates that it may be worthwhile to put more effort in the investigation on the effect of such science to public events. From the perspective of Brossard and Lewenstein’s framework on public engagement with science, the Chemical Christmas Show primarily achieved “inspirational” and “attitudinal” outcomes, rather than deep conceptual change. ³¹ While factual recall was limited and sometimes inaccurate, the event succeeded in enhancing curiosity and fostering a more positive perception of chemistry and its practitioners.

Integrating such events into the curriculum and student training can also provide significant added value. Students had already been actively involved in previous shows. While their positive experiences had previously been perceived subjectively, they were now objectively confirmed by the small survey. The results suggest that actively participating in a science show can offer valuable learning experiences, especially when integrated into coursework. Students particularly emphasized the added value of preparing experiments for the audience. They highlighted the importance of handling hazards and conducting risk assessments, which had to be adapted to the venue and stage—an aspect less common in standard laboratory work. This experience allowed them to effectively apply the theoretical content from their teacher training courses in practice. Additionally, they reported investing more effort in developing the experiments due to the highly diverse target audience. Beyond scientific skills, participation in the show also appears to foster the improvement of personal skills. Some students reported increased self-confidence and an improved ability to manage nervousness. These findings support the idea that including students in the design and execution of such events can be beneficial—not only for the audience but also for the students themselves. Engaging in these activities helps future chemistry teachers develop essential skills, such as designing and delivering experiments tailored to specific learning and target groups (Figure 3).

Figure 3:

All participants of the 2024 Christmas show on stage (Copyright: Angele/University of Graz).

These findings align with Self-Determination Theory (Ryan & Deci, 2000), which predicts that contexts offering autonomy, competence, and relatedness can foster intrinsic motivation and sustained engagement. The students’ reflections on self-confidence, risk assessment, and audience interaction directly map onto these needs. Furthermore, the affective and psychomotor competencies reported—such as public speaking, improvisation, and stress management—are consistent with Anderson and Krathwohl’s (2001) expanded taxonomy, suggesting that performance-based outreach activities can address dimensions of teacher education that traditional laboratory instruction rarely reaches.

The aim of the study reported here was to gain insight into the learning effects of a chemical Christmas show or lecture. It is important to note that the present study is based on a simple, ad hoc survey with a comparatively small sample size. Consequently, the results can only be generalized to a limited extent and cannot make any definitive statements about the impact of such shows. Nevertheless, the results show that it can be worthwhile to take a closer look at the impact of such chemical shows and chemical Christmas lectures. Overall, these results also show that the communication of content and knowledge at such events is not particularly successful. However, the finding that the image of the university and its researchers can be improved through such formats is promising. This opens new opportunities to improve these 200 year old science communication events.