This comes up every year, so posting for anyone reading.
Yes, it is unethical. You harm another family directly by trying to benefit your own family. It also undermines community cohesion by having schoolmates not live nearby, and it harms the environment as larger distances need to be travelled.
But really, it is wrong because you hurt someone directly for your own child's interests. Caring for your child is not an excuse to directly hurt another child and take from that child what you want for your child. Period.
And to those who say 'but everyone is doing it' or 'likely to take a spot from another renting family' - That is an attempt to justify your situation and downplay your ethical dilemma - its a natural response to your cognitive dissonance - you don't want to think of yoruself as a bad person. But it is not true, an it is not helpful.
Not everyone is doing it. Some of us beleive in respecting our neighbours and others and won't directly hurt them to benefit our own kids. And what kind of moral code do you follow anyway if you truely believe that if many peopel do something unethical then its OK for you to do so as well?
It is also incredibly unlikely that you take the spot of another strategic renter. Less than half of the spaces will be taken up by strategic renters we can guess. And those renters won't be renting on the edge of the catchment, they'll rent as close as possible to be certain. You will take a place from someone on the edge who likely has been living there a lot longer and deserves the spot.
Its worse though - you are likely to be able to afford private school, or to move to another community altogether where schools are more to your liking. The person you take this space from probably can't. So you likely give them fewer options than you have by doing this to them.
So not only are you taking from someone what they should have because you want it for your kid, but you leave them with fewer options than you would have if they are not as wealthy as you (most likely the case).
The statement above that it 'might not be in the spirit of the law' but is legal is damning - if you admit it is not in the spirit of the law then you are admitting it is unethical and wrong. Yes you can get away with it in some places. But please admit you are being unethical and hurting someone - stop denying it or making excuses like 'its ok if its for my child'. Its not OK to take something away from someone else if it is for your child. Please recognise that.