I've found that my DS picked up using the spoon a whole lot quicker if we were eating yoghurt at the same time - with a spoon. Then he copied us and learnt better skills...

HTH!
We had no luck getting DS "taught" however once he went to childcare (at 2!!!) he became much better at it! His dexterity improved tenfold just by watching other children, so I definitely recommend Nettie's idea!