When children learn to read they learn to solve a code. In English the code we use is called the alphabet. It consists of 26 letters. These letters are combined to represent sounds. There are 44 sounds in English and more than 200 ways of writing them.
There is strong evidence that, when the correspondence between the sounds in English and how they are written (sound-letter correspondence), is taught in schools, children become confident and fluent readers. Synthetic phonics is an approach that teaches children to read words by saying the sounds the letters represent and blending (pushing) those sounds together fast, from left to right throughout the word to read the word. Children also segment the words into their separate sounds.
Children discover that sounds can be spelled in more than one way and by one or more letter e.g. the sound /ie/ as in tried, can be written like this: ie, y, igh and i.
Speech pathologists can work on an individual level with children using a synthetic phonics approach while adapting the pace to the child’s needs. Speech pathologists can help children who are struggling to read to say sounds correctly. Some children, for example, may confuse /a/ with /e/ in their words. If they cannot match the /a/ to the way it is written, they will struggle to read words with that sound in it. e.g. they may read bad for bed.
Check out this link for data from a school in the UK that uses a synthetic phonics approach in the classroom, called Sounds-Write: http://www.iferi.org/iferi_forum/viewtopic.php?t=528#p1479