There will definitely be other ways to do this, but I think it makes pedagogical sense to use the same fingering as usual, ex. as in the C major scale, unless there is a need to change it.
I understand Desordre's idea on letting the student figure it out themselves, but in my experience, this leads to problems later on. I have become convinced that a solid, consistent fingering is a necessary requirement in confident scale playing. I definitely do not advocate additional complexities when learning something new, but fingering is worth it, especially when students are required to play fast, and with good tone.
The fingering itself is not important; the important thing is a logical consistency among all technique patterns that students can grasp hold of when their muscle memory fails them.
The normal fingering works well in the R.H.

L.H. does not work with the normal fingering.

I see two options that will overcome this.
1) start on finger #3 (As you would for the 6th note of a D major scale) and continue on with the D major fingering. This reinforces the relative relationship to D major.
2) Probably simpler, use the same fingering as a B major scale (4321, 4321, 321...)
It depends on how strongly you associate the minors with the relative majors in your teaching of technique.
Hope I've helped.