From a practical point of view, there are four particular areas that need to be taught: taxying, flying, landing and navigation.
Before you even start flying, though, there are things which need extra consideration. Allow time for your eyes to adjust. (You'd be surprised at how many students, after being briefed on this subject, will walk outside to pre-flight an aircraft, then walk back into a lit room immediately prior to flying.) And discuss the use of a torch for the pre-flight.
When taxying, emphasise how difficult it is to find your way around an airfield you don't know. (If possible, take them to an airfield they don't know.) Discuss taxy speed, use of taxy light, not cutting corners, airfield lighting. Keep rpm high enough to keep the alternator working, dab the brakes periodically to control speed if necessary. Another subject for discussion is the lack of peripheral vision (and, for example, the difficulty this poses in detecting movement outside when you are heads-in doing power checks).
On the flying, the main thing is the need to use the AI to back up the visual horizon. If possible, find a specific place near your home airfield where you can demonstrate this particularly well (e.g. a town behind a hill). Also discuss the problems of forced landings.
The biggest problem I had is height perception during the flare. I got over this initially by using the landing light to judge when we were close enough to the runway to begin flaring
The single most important thing, from a practical point of view at least, to teach in night flying is
not to use the landing light to judge the flare! For this reason, always start with the landing light
off for landing, and only allow the student to turn it on once he has learned to land with it off.
On the same note, ask ATC to turn the runway edge lights down to their minimum brightness, and turn off all other runway lights (approach lights, PAPIs, etc) when teaching night landings to a new student.
As for navigation, there is a mandatory element of navigation in night flying, and I think the best way to use this is to get the student to plan a navigation leg using only visual navigation techniques. The aim should be to demonstrate how difficult it is to navigate visually at night, and suggest to the student that it is not a good way of navigation, and that navaids should be used to back up visual nav whenever possible at night. (There is no need to teach navaids, since the student should be familiar with them from his PPL anyway - and if he's not, they can be taught during the daytime just as easilly as at night.)
Away from the practical side of things, you say you are not teaching in the UK - but are you teaching for the UK qualification? If so, students must understand that night flying in the UK is always IFR or SVFR, and understand the implications of that (quadrantal rule and the 1000' rule outside controlled airspace).
Those are the main points which spring to mind, although I don't have my notes with me, so I may have missed something. Have fun - I think the night qualification is one of the most enjoyable qualifications to teach for!
FFF
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