When I think back I’m astounded to remember how often the slipper was used when I was at school. I went to a catholic comprehensive boys school in the 1970s/80s and it was literally given to someone in front of the class every other lesson. I once saw about 30 boys slippered in the gym hall for having the wrong item of PE kit. Thank Christ my gym kit was OK. I was slippered in class a handful of times over 5 years. I just got one whack on each occasion, but it stung like hell and literally brought tears to my eyes. I dread to think what it would have been like over just gym shorts.