Secondary Moderns.

When I was on my first teaching practice in 1974 at what was indubitably the worst school in Rotherham, and possibly the whole of South Yorkshire, I recall an interesting conversation with a teacher who had been there both when it had been a sound secondary modern and later, the atrocious comprehensive I remember today with such horror.
This school actually achieved significantly poorer results as a comprehensive than it ever had done as a secondary modern!
[This dreadful sink school, serving a working class area, became so poor that Rotherham L.E.A. eventually had to close it down.]
If you take into account that as a comp, it had kept the top 20% or so which it had never previously seen, this diminution of standards is little short of amazing and yet, was not all that untypical.
This scenario came about because the 'dumbing down effect' had kicked in to the detriment of the more intelligent pupils who then simply sank into the mass of unmotivated mediocrity.
Work, which had been the norm in a grammar school, could be a cause for victimisation in the comprehensive.
Tellingly, there was another great loss for those pupils who had formerly been the 'top dogs' in a secondary modern. According to my informant, these pupils had constantly been motivated by saying "You are not going to let those grammar school kids do better than you - are you?"
These same children saw that motivation removed and inspiration destroyed.