Do we know that for sure? Besides, Eishes Ish, from a halachic standpoint, is transgressed only in an extreme circumstance – for all we know, this teacher “touched” a student inappropriately, but did not cross the line to qualify as Eishes Ish.
Obviously, I think what she did was very wrong, but the emotional scarring is much worse when the perp is of the same gender as the victim.