As far as I can see, no, it is not:
"3. I reject as acceptable all sexual activity not in agreement with the Bible, including, but not limited to, premarital sex, adultery, and homosexuality."
The school is asking employees to profess the principles of Biblical sexual morality, not pledge to be sinless in that regard. No Christian should have a problem with that.
On the other hand, the pledges indicates that the signer promises to not drink in public, presumably in accordance with the school's theology, and as examples for the student body. Strict but not unreasonable given the school's beliefs.
What do you think that “premarital sex” meanss?
The title misrepresents what the pledge is actually asking them to do. They are not signing a pledge that says they are not homosexual. They are pledging that they reject as acceptable any sexual activity that is not Biblical. Specifically listed are premarital sex, adultery, and homosexuality. And the pledge is qualified by saying “including but not limited to” these three. So presumably they might also consider masturbation or some other sexual practice as being required to be rejected.
And homosexuality isn’t even the first thing that is listed. The top of the list is premarital sex—because most people are heterosexual so that is the more widely practiced perversion of Biblical teaching.
Welcome to FRee Republic.
Your response at number 52 is self-contradictory.