When a child gets into a school nobody is being deprived anything because a child is being taught. Silly
If the school is over-subscribed, as is often the case with faith schools, the lying family may well force out an honest family.
That is morally wrong.
Lying and cheating to obtain an advantage for your own is also morally wrong.
Making your child participate in the deception by rehearsing lies, is despicable.