Not that I support caning by random teachers; this happens a lot of developing countries. A random teacher becomes the judge, the jury, and the executioner.
A caning punishment with proper investigation from proper authority seems like a good middle ground. Bullies should be punished. We cannot just brush it off as "they are just kids".
Life time physical or emotional scarring would, to pull out an example, be US slavery degree.
I grew up when corporeal punishment was a thing in schools. No physical or emotional scars.
Wish this is extended to white collar crimes.