Rhyme is a fairly simple way of communicating.the concept of the sounds of vowels. But vowels cannot be learnt without the accompanying consonants. So it is not practicable (or desirable) to teach either vowels or consonants in isolation. Teaching vowels by themselves is like trying

The first stages

to teach the different uses of an 'anonymous' sound like that of the 'e' in 'the'. The main advantage of teaching sounds in terms of rhyme is that it draws attention to the' middle of words rather than just the beginnings. The traditional link of 'a' with apple, or's' with sun does not necessarily lead the child to understand the same letter in a different position. It is worth teaching the sounds of letters in the middle, or the end, as well as at the beginning of words.