I remember having some Observer books back in the 60s - Birds, Music and Art. The Observer Book of Music was written, spookily, by Freda Dinn. A quick check on Google confirms this, and also my vague recollection that they were published by Frederick Warne (who also published Beatrix Potter, and it shows).
Nothing at all to do with Collins Little Gem, which were, and still are, dictionaries, or Ladybird Books, mostly readers/factual books for younger kids.
A couple of months ago I was standing around the school grounds feeling vaguely autistic when a six year old kid (nearly seven) I'd never spoken to before came up and started explaining to me the difference between newts and lizards. Yay!! A little professor! I'm now teaching him chess (which I think he'll strugggle with) and informally mentoring/shadowing him. His current diagnosis - though he has another appointment coming up, is borderline AS.
I know a few other 'little professors' as well. I was probably too shy and withdrawn as a kid to come across as one myself.
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It's not just what you're given: it's what you do with what you've got
(Si Kahn)