To answer your questions, just imagine that it had been a 17-year-old girl and a 21-year-old male teacher, but that the other particulars of the case had been exactly the same. Now: Do you think that a judge would cut the male teacher any slack because the girl was "willing," or had "previous experience," or had "bragged about it" to her other girlfriends? Can you imagine the statutes in a lawbook prohibiting sex with minors, but granting exemptions because the minor "had already been around the block a few times?"
Regards,
The standard is different because females get pregnant, so it’s more serious if the student had been a girl.
On the other hand, other than a breach of professionalism which should cost her her career, this should not be a criminal issue.
Only becomes a criminal issue in a feminized society, where the law erroneously views the sexual behavior of males the same as of females.