Pupils no longer put right out of sight (8)

I believe the answer is:

obscured

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'out of sight' is the definition.
(I've seen this before)

I can't explain the remainder of the clue.

(Other definitions for obscured that I've seen before include "Concealed from view, made indistinct" , "kept out of sight" , "Overshadowed or eclipsed" , "Hid from view" , "Good news from clinic about schoolboy no longer" .)

I've seen this clue in The Sunday Times and The Times.

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