I'm with e2efour on this. It sounds a bit strange. Also, you definitely need to get rid of the word "the."The aim of the teaching is to drive/ propel your pupils ahead.
Is the phrase 'drive/ propel your students' correct if I want to mean that a teacher should encourage his students to move ahead in life?
Hmm...I can think of several options here, but none of them seem them seem to be exactly what you want.The meaning which you gave of ' drive someone ahead' that to move someone further along the road of knowledge. This is what I want to mean
Do you mean "propel" are always confined to be used in launching a spacecraft?Propel is rather a violent word (think of propeller, propellant), so it would hardly be suitable in your sentence (I assume you made it up).
Without knowing what kind of teaching is involved, I don't really know what is mean by drive ahead. It should mean something like to move your pupils further along the road of knowledge. Nor do I really understand in practical terms what is meant by move ahead in life.
The aim of the teaching is to equip the students with knowledge that will enable them to get a better job (one interpretation). You don't encourage people to do this, you enable them.
If we use this to show a person's determination, e.g. He propels himself forward, would it be exggerated and therefore incorrect?No, but there is usually an idea of moving someone or something forward using some force. For example, you can propel (or drive) a boat through the water with oars.
I see. Is it natural to say propel something, but unnatural to say propel someone?It would sound very odd to me. "He pushes himself forward" is what I might say (in the sense of pushing himself forward from a group of people). Or "he drove himself day and night, trying to learn the irregular verbs".
You cannot use incorrect since we can always use words metaphorically. But you can use unnatural.
I see. I notice the key to understand the usage is that you cannot use propel to mean encourage or boost.Not necessarily. For example, He was propelled to alcohol (=he was driven to drink) or (from the BNC) It was probably the affairs of the East India trade that propelled him into politics (=drove him into politics).