Question:

If Zaid doesn’t get any evil thoughts when a non-mahram woman comes face to face with him, nor is there any fear of fitnah and fasad, can Zaid teach his non-mahram female relatives books like, ‘Taleemud Deen’, ‘Heavenly Ornaments’, and ‘Islahur Rusoom’?

Answer:

It is best that a woman teaches a non-mahram woman. A male should not teach. If there is a dire need, then never teach in seclusion. Rather, teach along with a group of women and maintain the laws of hijab (partition etc.).

And Allah knows best.
(Hazrat Mufti Maulana)  Zafar Ahmed Thanvi (May Allah have mercy on him)
Imdadul Ahkaam Vol.4 Pg.405