Look for a couple of same-shaped items that are familiar to baby. Use various words to compare how the items differ from each other. You might say “Look at these crackers. This one is a square cracker. This one is square but it is brown. Look how this square cracker has little holes in it. Here is one with a bite out of it!” These introductory experiences with differences in objects may help your child later as they discover what is the same and what is different about letters. All of this adds to their letter knowledge, which is part of early literacy.
–Tip by Jan P., Preschool/Childcare Liaison