Teachers bring their own knowledge gaps to the classrooms
Teachers study to become teachers. Part of their studies focuses on methods, but a big portion revolves around the topics they are meant to teach later on. If during the formative years there's a knowledge gap, it is extremely likely that it will manifest during a class. This can be seen, for example, when teachers neglect topics such as physics or chemistry in favor of humanistic subjects[@furman2020Aprender ciencias en las escuelas primarias de América Latina].
The lack of sufficient knowledge and biases at the teacher level could be one of the explanations for the correlation between pedagogical approach and science education outputs, mostly because of the correletion between time spent and competency in scientific literacy. However, knowledge gaps can also explain why teachers lack tools to design a science curriculum.
After all, teachers are people who went to the same education system than the kids they are educating. It is understandable that there is a self-replicating problem that needs some form of external intervention to change course. This may be exactly why incremental change leads to unsustainable educational paradigms.
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