I checked
My Early Life, and the passage referred to above does not in fact appear in that book. Rather, it is in a letter from Churchill to his brother, reproduced as follows in
Winston S. Churchill, Vol. I (Youth: 1874-1900), by Randolph S. Churchill:
I am sure you will be horrified by some of the Regulations of the Military Academy. The cadets enter from 19-22 and stay four years. This means that they are most of them 24 years of age. They are not allowed to smoke or have any money in their possession, nor are they given any leave except two months after the first two years. In fact, they have far less liberty than any private school boys in our country. I think such a state of things is positively disgraceful, and young men of 24 or 25 who would resign their personal liberty to such an extent can never make good citizens or fine soldiers. A child who rebels against that sort of control should be whipped – so should a man who does not rebel.
Plus ça change, plus c’est la même chose.