Thomas Wilhelm, who has won several awards for his approach to teaching physics, explains why physics lessons sometimes aren’t very successful, and how we can improve them – using computer programs, for instance. In January, new online teaching materials on “motion” were made available to schools.
UniReport: Professor Wilhelm, most schools don’t implement the ideas for teaching physics that come out of research – something your doctoral student Jakub Knebloch discovered during his interview with teachers. The reasons they gave were “We don’t have enough time” or “The suggestions from university didactics are too ambitious and unsuitable for everyday school lessons.” What is the problem – is it the situation in schools or the teaching ideas that come from the university?
Thomas Wilhelm: One thing I want to make clear directly is that we are not engaging in any kind of teacher-bashing. Many physics teachers are passionate about their subject and work very hard at transmitting it to their students. Be that as it may, we still find that many of these basic ideas don’t “get” to the children during lessons. Even after finishing a class on a physics topic, they often have the same misconceptions as before.
So, children come to lessons with misconceptions?
What I mean by that is that they come to their physics lessons with everyday conceptions – about what constitutes force, energy, electric current, heat and light, for instance. These ideas are quite different than the concepts used in physics.
Could you give an example…?
For instance, we think that we see because we look at something; in physics we learn that the object emits light that reaches our eyes. In colloquial German we say we need “Kraft” (“force”) to do something; but in physics we learn that one cannot “have” force, and that a force only exists at a particular moment during an interaction. What this shows is that everyday language and the technical language of physics don’t match up. That makes learning physics so difficult – you constantly have to re-learn things.
Does that mean schoolchildren’s initial ideas about physics are wrong?
When beginning a topic, it’s not really advisable to tell them that physics ticks differently than they do. It’s better to start with ideas that are more or less correct and build on them.
Are physics teachers aware of that?
They didn’t use to be, and most assumed that children had no prior knowledge and it would therefore be simple to teach them the ‘ways of physics’. As a result of these special difficulties, physics was one of the first subjects to investigate pupils’ preconceptions, as early as the 1970s. This means we now have teaching concepts that take into account these learning difficulties. My colleagues and I have developed many such concepts and, most importantly, tested them empirically in actual lessons. I have meanwhile also published a book outlining concepts that differ from the traditional ones. Nevertheless, some very old concepts continue to be used.
After coming to Frankfurt in 2012, you founded a “schoolchildren’s laboratory” – today, some 4,000 children come here each year, making it Goethe University’s largest laboratory of its kind. You use it both for teaching and to research these new didactic concepts.
First and foremost, the schoolchildren’s laboratory is of course a service for nearby schools. As such, we introduce children to topics that the schools often don’t have time for. But the laboratories are also good places to conduct didactic research, whereby we take into account both sides: We examine how teaching concepts are accepted by the pupils, and we survey the teachers.
You like using computers, tablets and smartphones in physics lessons, which some teachers might dismiss as simply too much. Be that as it may, the cooperative project you implemented with the Hessian Ministry of Education and which ended last year will offer teachers a lot of free materials on the topic of “motion” from 2025 onwards.
For my Habilitation I was already researching how schoolchildren can analyze and visualize motions that are previously filmed. A computer program records where the object is at what time, what its velocity and acceleration are, and what forces are acting on it. So, we’re dealing with real, filmed motion and no longer with small objects moving along the lab bench. In January, we made available on our website new tutorials, videos and worksheets for use with iPads.
Your doctoral student Jannis Weber has researched in more detail how computers can be used to help children learn about mechanics.
Yes, one option is to film a motion and then measure its course. Another way of approaching the topic would be to consider a particular motion and which forces are involved, and get a computer to calculate how the object should move. Then we can check whether the motion visualized on the basis of our calculation really is what we observed. This approach allows children to learn something about motion and forces by gaining access to both topics in a totally different way. To answer the question of which of the two methods is more useful, we carried out identical experiments in the schoolchildren’s laboratories. Many had expected the youngsters to enjoy experimenting and anticipated that they would find it boring to use computers for the calculations and modelling, both of which most would not understand. In the end, the result was an entirely different one. There were hardly any differences between the two children’s laboratories: The children learned a lot in both and had just as much fun.
Why are new concepts like this not yet used in many curricula?
As part of the teachers’ survey I mentioned, my doctoral student discovered that many physics teachers simply aren’t aware of these new teaching concepts. They never encountered them – neither as students not as teachers – also because no special channels exist for disseminating this information. The second problem is that the curriculum is simply full, making it extremely difficult to prepare and introduce new things. Other aspects here are too many regulations, too high a workload, et cetera. The third point is that some teaching concepts developed by educationalists at universities are just not practical in the classroom – making this an issue that has nothing at all to do with the teachers, but with the didactic theorists, who don’t publicize their ideas enough and also don’t ensure that they can easily be put into practice in class. We are now starting to see our empirically tested concepts slowly finding their way into the school curricula. As such, the concept for introducing mechanics and the one for electrical circuits are now on the curriculum in Hamburg, Bavaria and Austria. In some parts of Germany, however, this process is taking longer.
Why is that?
There are some federal states where an expert commission scouts good concepts and then prescribes them in schools. In Hesse, on the other hand, there’s only a core curriculum at secondary level I – leaving the teachers a lot of freedom to decide what they teach, how, and when. The schools are then required to draw up a school curriculum – which becomes a problem because there’s no time to read the research literature…
So, this freedom sometimes results in everything staying the same?
If a school has teachers who are interested in research into didactics, they can have a very modern school curriculum. In my view, however, many schools are unable to cope.
For the first time since 1980, a female physicist has now been awarded the Robert Wichard Pohl Prize by the German Physical Society (DPG) in recognition of her achievements in the didactics of physics. You, Mr. Wilhelm, were awarded the prize the year before. There are also several other Frankfurt laureates. The latest among them, Rita Wodzinski, who has been researching and teaching at the University of Kassel since 2000, earned her doctorate in Frankfurt – meaning she received her didactical introduction here. Is Frankfurt particularly strong in the didactics of physics?
I wouldn’t like to pass judgement on our work right now. But maybe the candidate fits in with what I said before. Starting in the 1970s, and well into the 1980s and 1990s, Frankfurt took the lead in investigating children’s preconceptions and using them as a basis for developing new teaching concepts. People know about the concept for mechanics, for example, on which Ms. Wodzinski wrote her doctorate in the 1990s. This concept has now been introduced as mandatory in some German states – illustrating just how long it can take for something to reach the classrooms – 30 years in this case.
Looking forward to the next few years – what new lesson concepts come to mind?
We never run out of topics – climate change is a current one. The University of Innsbruck has just developed a concept for teaching “greenhouse effects.” One of my doctoral students will now examine the concept empirically in a school setting. We are hopeful that it won’t take thirty years this time for the concept to arrive in the classroom.
