For my school, we have strict school rules because it is an all-boy school.
You did not like getting the same punishment as younger boys? Why? Older boys might be expected to set a good example to the younger and to be more responsible. Older boys are more culpable than younger. The cane is more severe for a small boy than a larger one.
Are you not supposed to go to the toilet between classes or are you meant to get a pass for this? I think the older students should talk to the headmaster about this rule. It needs to be relaxed.