Learning ABCs involves being able to see and recognize the small differences in the shapes of letters. Some stepping stones on the way to recognizing alphabet letters is learning to recognize shapes, paying close attention to the details in pictures, and comparing and talking about differences and similarities in objects.

Mommy, where are you? by Leonid Gore is a good book to use for practicing visual discrimination. As the baby mouse looks for his mommy, he keeps seeing shapes and colors that are like those of this mother. He repeatedly thinks he's found her and then more of the shape is shown and he realizes it is something else that shares only some characteristics with his mother.