There is little time within the early stages of engineering education, to devote an effort to problem modelling; students are just trying to cope with the multiplicity of subjects, with little time for reflexion. For that reason, it is not a surprise that, when offered some choice of term problems, students tend to choose the more explicit ones, however difficult they may be, against simple statements that would demand making working-hypothesis, approximations, assumptions... modelling, in a word.
A model is a representation of a reality that retains only the salient features the modeller wants; there are no true or false models, but suitable or unsuitable models to the purpose at hand. Modelling approaches what Prof. Polya said about Geometry: the science of correct reasoning on incorrect figures.
Learning how to model problems is perhaps the most difficult task in problem solving, demanding creativity from both students and professors, to find the master guidelines in the process, avoiding the idea that modelling is having 'lucky ideas'.
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