Now I'm all for a good solid education and schools making studies a priority, but this principal is missing a small piece of reality here - has he not read Romeo and Juliet?
You can't 'ban' teenagers from anything. In fact, the more you ban something, the more likely they are to take it up. Understanding teenagers means understanding they will do what they want, whether you like it or not, because they always know best.
Trying to tell them they don't know best, and that they're only using a tiny portion of their still-developing brain, is futile. Trying to ban something, is even more futile.
Talking to teenagers about what you disapprove about them, is about as helpful as trying to explain a time before cellphones. They don't get it. They won't get it. It falls on deaf ears.
I'm no expert, but in my experience with teenagers, the more you talk about the evils of something, the more you're selling it to them. That's before we get to the bit where last time I checked, people's personal lives were not a school's business.
Their grades, uniform, behaviour in class and attitude towards teachers is the school's business, sure, who they choose to kiss, is not. And that's before we get to the expectations of the teachers here.
Don't they have enough on their plate these days? And now at this school, they're also expected to patrol any signs of amorous behaviour?
So what constitutes an expellable relationship? What does that amount to? A sideways glance in maths class? Flirtily offering to loan someone your pencil case? Walking someone to the playground?
Because I can guarantee you if you pull a student into your office and ask them outright if they're in a romantic relationship, and they know that relationship is banned and that they may be expelled, then guess what that teenager's going to say? "No Sir, not at all. We're just friends."
So all you're actually doing is teaching them to lie.
I would have thought if policing relationships in order to cut them off was your thing, then perhaps a single-sex school might make things a tad easier?
If your school is a petri dish of teenagers and hormones, you can only expect one result. So instead of an antiquated draconian outright ban, perhaps teaching the merits and values of consent, appropriate behaviour, and respect might be a more useful approach.
Raising teenagers is a lot like training a puppy (I'm currently doing both), in my experience, tell them what you do approve of, and you'll usually get better behaviour and results than shaming and banning them. So to the principal running this policy, it's a D- from me.