One useful way to think of each year of chem/science study is to assume _it's the last year this student will take the subject_. From that perspective, the stu

One useful way to think of each year of chem/science study is to assume _it's the last year this student will take the subject_. From that perspective, the student will spend the rest of their life with _this_ mental model. When viewed like this a mental model of a nucleus with electrons 'orbiting' around it is entirely valid and literally drops the student in the early 20th century. One of the problems with experts is that they try building a straight line from zero to expert that never needs a backtrack step. Personally I like the opportunity for students to learn about the experimental evidence that _forces them_ to need a better theory than the one they've come in with. Cognitive dissonance is one of the most powerful forces students have for learning - a good teacher should be engineering these moments as part of their lesson design.