The biggest problem I have as an Instructor is relating the theory to the practice. The topic starter question has very little relavance to the operation of a light aircraft.
I want my students to understand what the major parts of the engine lubricating system do, but more importantly understanding function in the context of what is a normal indication of the oil temp/press guage and what is not.
So for example on a cool day we expect the engine oil pressure to intially be near the maximum because the oil is cold and thick. As the engine runs we expect to see the oil temperature rise and the engine oil pressure to drop to the mid range as the oil warms as well understanding that idle oil pressure will be lower than runup and higher RPM operation. In other words I expect the student to be aware of the connection between oil temperature and pressure and RPM. So for example they would know in a hot engine that idle oil pressure in the yellow (low) range is normal but the same indication during a runup (or worse inflight) would be immediate grounds to terminate the flight.
I also review the expected engine guage indications that one would see for the likely emergencies of low oil quantity, oil pump failure, congeled oil cooler, and an inappropriatly bypassing oil cooler.
Finally I emphasize the importance of monitoring guage trends. It is not good enough to say the guage is "in the green" the student must be monitoring the value ( or the relative needle position for those horriblle Cessna/Piper guages with no numbers
). So for example iif the oil pressure in cruise started at the high end of the green arc but is now at the low end of the green arc it is time to starting thinking about what would cuase this and understanding this could be an early warning of an engine failure... even though the oil pressure is still "in the green".