In my day (elementary school in the 40s) corporal punishment was common in the public school I attended. Heads slammed by books (for talking), ears pulled (usually reserved for boys), heads pushed by the chin against blackboards (they were really black then, not green), and occasionally, a mouth washed out with soap. I never heard of parent protests although I’m sure there were some.
We had corporal punishment when I was in school but I never knew of a kid with a black eye. They used the “board of education” on the seat of the pants. That was it.