Helping students with micro-macro thinking in chemistry
How do classroom demonstration experiments help students learn chemical reasoning? Marie-Jetta den Otter, PhD student at ICLON, researched this. She defends her thesis on 6 December.
From small to big
A new exam programme put more emphasis in chemistry education on developing structure-property reasoning (SPR). Secondary school students are beginners in chemistry. They are oriented towards the observable world around us, the macro level. With micro-macro thinking, they have to explain the properties of substances like water or petrol at the macro level. They do this with the level of particles. These particles cannot be seen with the naked eye, which is why we call them the micro level. Students find this way of reasoning difficult to learn.
Doing experiments
Since particles cannot be seen, models are used. Students find it difficult to deal with the limits of models. This creates misconceptions and difficulties in learning micro-macro thinking. Scientific research shows that showing chemical phenomena in class helps teach this type of reasoning. Teachers show these chemical phenomena in demonstration experiments and then explain them at the micro level. Thus, they encourage the development of micro-macro thinking in students.
Research in your own classroom
Marie-Jetta den Otter is herself a chemistry teacher at a secondary school for two days a week. 'As a teacher at a scondary school, you rarely come into contact with education research and the associated theories. Immersing myself in this was enjoyable but also challenging, I found the theories on how the learning happens and how the teaching happens the most enjoyable and interesting. But switching between research and teaching was difficult. However, even more complicated was performing this dual role simultaneously: conducting research in your own classroom. It caused an overload of my own working memory.'
Predict - observe - explain
'Hopefully, the results of this research will find their way into the classroom. I hope that the results will improve the use of demonstrations by teachers, now incorporating a Predict-Observe-Explain (POE) task. That is: predict the outcome, observe the experiment, explain the observation.
Additionally, I hope that the perspective for micro-macro thinking will better support teachers and students in learning chemistry. Lastly, I hope that the SPR instrument, including both a sorting task and a mapping task based on the perspective, can be used for formative assessment. There are still many exciting opportunities for the results and for me.'