How to teach students to work with multiple layers of abstraction?
Link to real life

“Who has came to school by bicycle?”
“OK so we need to know how to make a bicycle”
“What time did you get up? It must have taken a long time to build the bicycle?”

Take it to the limit; be absurd. So the pupils tell you “You don't need to know all this to get to school.” Agree with them.

“Any one here ever fix a bicycle?” — “yes”
“So you have to fix it every time you ride?” — “no”
“But you do have to think about how it work, the inner tubes, the oil, the gears, every time you ride it, right?” — “no”
“Why not?”

Link to past experience, in subject

“Now what about a print statement, we need to know how that work to be able to use it, right?” — “no”

“So over the next few days/week we are going to be looking at a more complex system than before. We can not hold it in your head all at the same time. So I am going to ask you to do what the professionals do: don't try to remember/understand it all at the same time. We only need to understand ‘how’ for the bit we are working on. It is enough to understand ‘what’ for the bits that this uses”



This is only the 1st draft of an idea, and not tried with a class.