During playtime in my chaotic young 5' classroom I was working one on one with a little guy who has problems with identifying the first sound of a word. The game I was using has pockets for each letter and game pieces with items to name. As I showed him an item he'd name it and I'd prompt with, "first sound?" We'd then put the picture piece in the appropriate pocket.
After about 20 items I showed him a picture of a horse. "Cow," he declared.
"No, it's a horse,"I corrected.
Long pause, "First sound," I prompted,
"OK, you can go play."