For good:
My Infants' School teacher, Mrs. Porter, who greatly encouraged my reading - even sometimes lending me her daily newspaper. (I would not have understood the people and matters reported, but could easily cope with adult vocabulary even at that age. By "adult" of course, I mean "grown up" not immature pornography or swearing!)
When my Dad's work move forced us along with many other familes to move to a different county, my teacher's farewell gift to me was a copy of A.A. Milne's Winnie The Pooh, in which she signed the flyleaf with her name and "Keep on reading".
That was in the 1950s, and Mrs. Porter was very advanced in many ways, I recognised many years later.
One innovation of hers, which I have never seen anywhere else, was to arrange our tables (not traditional desks) in conference fashion, along the walls with a gap by the door. So we could all see not only the teacher and blackboard, but also most of the rest of the class; encouraging many of us really to inspire each other as well as be inspired by the teacher. The central area was left clear for less formal activities on the floor.
For bad:
Two successive Mathematics teachers in the state system, local education-authority grammar-school.
The first, teaching us in the Third Form (age 13-14) was in his last year before retiring. Probably worn out by years of trying to make motley collections of adolescents understand maths well below his own level, he was little better than a talking text-book. It mattered not the topic - algebra, trigonometry, mensuration, pure-geometry, proportions - he was unable to make any of it interesting. Nor suggest any real-life purposes for such calculations, routine in so many areas of work and even craft hobbies.
He would probably help anyone who asked, but otherwise he did little more than demonstrate the technicque on the board, then set us part of the exercise in the text-book. Of inspiration, there was none.
I forget his name, but anyone familiar with Carl Giles' newspaper cartoons will have a good idea if I say he reminded of the "Mr. Chalky" teacher character.
The second, for the Fourth and Fifth Years (ages 14 - 16) was, umm, let us be kind and say eccentric. Actually he was not a nice man at all. He was arrogant, even bombastic, and suffered no fools gladly: his definition of a fool including anyone who disliked and struggled to understand maths. We knew him as Mr. Hill, and "Sir", to his face but behind his back used his bizarre nick-name "Drasher", apparently bestowed by his fellow cricket-club members in years past.
The Fifth Year ended in the General Certificate of Education "Ordinary Level" examinations, and good passes in these could help you obtain good work including an apprenticeship for those leaving school at sixteen; or a place in the 2-year Sixth Form (16 -18) to study your three chosen subjects to GCE "Advanced Level" designed as entry qualifications to University.
So the Fifth Form particularly was a key year. This teacher though, was interested only in the bright, keen ones able to understand easily all of the many topics, and needing only some extra help here and there. He probably wanted high exam pass rates, to show his ability as a teacher, and basically disregarded we who struggled. *
"Drasher" could explain everything quite well, but assumed everyone could grasp it straight away, and had no patience with anyone who found it hard. He wrote on one of my Reports (my parents had kept them) that I had large gaps in basic understanding that needed attention; but he had never mentioned it to me, never offered help, and I felt unable to ask him for help.
...
There is a bizarre footnote to Drasher's life, revealed in a local history page in my local newspaper a few years ago. I wish I had kept it.
It recounted that as an athlete in his pre-War teens, Hill was in the England team for a prestigious European youth athletics event in the mid-1930s. Hitler had already assumed power and personally attended this event in London.
The story goes that when young Hill shook Hitler's hand in turn in the pre-play ceremonial, he managed to stand on Der Fuehrer's toe. No doubt accidentally, but I thought, "That's my 'Drasher' all over! "
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* The GCE O-Level Mathematics syllabus at Fifth Year level included Trigonometry, more advanced Mensuration, Algebra including linear and quadratic equations, simultaneous linear equations and graphs, Calculus (differentiation and integration), and Pure (or Euclidean) Geometry. We had to be able to use Logarithms and their Slide-rule relation as arithmetical tools, as this pre-dated readily-available, portable, electronic calculators - I still can!
I forget what else it held, but the 'Mathematics' syllabus was a coherent, single course. The curriculum did not treat each topic as an isolated, separate subject, as the American system seems to do. As far as know the UK's schools still keep this coherence although the contents and examinations are different from my 1960s era.