A FEW versus FEW

If I say "I have a few excellent pupils", that means I'm happy and grateful to have them.
On the other hand, if I say "I have few excellent pupils", it means I wish I had more of them!

A FEW indicates a positive count something like "it's better than none", but
FEW indicates a negative count something like "there should be more".

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Same goes to "a little" and "little".
A LITTLE indicates "more or better than none" or "a small amount"
LITTLE indicates "not enough to be important" or "not very much"/"almost none".

e.g
1) I have a little money for savings. :)
2) I have little money to spend today. :(