Unfortunately, this often leads to oversimplification to the point of falsehood. While simplifying, the teacher needs to keep in mind the big picture , and insure that the simplified beginning can be easily built upon later to develop the full complexity of the concept without requiring unlearning . Students need to be made aware that they are learning a simple framework into which the details can be fit later. Exposing students to a level a bit beyond that which they are expected to master, is not a bad idea. No two snow flakes are the same shape.
Warm air rises.
The same water goes around the water cycle forever. The oxygen - carbon dioxide cycle. Heat is caused by molecules moving. We get heat from Sun. Earth rotates exactly once in 24 hours.