In the UK a slip was sent to your parents if you got an after-school detention, it was not intended to inform your parents, but it did do so, it was more to do with gaining your Parent’s consent, and would have given them a few days notice, without the consent of your parents the School would have been unable to enforce the detention,
I wasn’t caned at school but I did get a few detentions, I don’t think my parents were informed in either case although I had to take the initiative myself and inform my parents of my detention as this was after school and would involve a late arrival for tea.
They may have appeared on report cards but as I wasn’t badly behaved there was no fuss made.