Some of the children who come to the Bloomfield Learning Centre (where I teach) still pronounce their consonants ‘suh’ instead of ‘s’. This is a bit surprising as ‘pure’ or ‘precise pronuncation’ is now a common to all synthetic phonic programmes in the UK.
Anyway – what to do about it? My 6 year old pupil knows the sounds of the alphabet and consonant digraphs. He has difficult blending sounds together and I think his extra ‘shwas’ (the extra ‘uh’) is not helping. He doesn’t need to start at the beginning of the programme but he does need to clean up his pronunciation.
Here is what I do: I make up a Sound Snap game. I make 4 cards for each letter of the alphabet. I get the pupil to go over the letters and say the sounds correctly. Of course, these can be introduced gradually over a number of lessons. Here is an example of making cards for the sounds ‘ch’ and ‘sh’- which many children confuse. We shuffle the cards and play Snap. Every time the player puts down a card they must say the letter sound with precise pronunciation. The children love this game. It can go home for practice. 
