Teaching your Baby about Shapes
Your baby (5 - 12 months) might be too young to say the names of the different shapes, but that doesn't mean you should't start introducing them! However, instead of using flashcards, get the shape involved in your play, so that she can experience it with all her senses, instead of just seeing it on a card. Tell her her plate is round, or the phone is a rectangle, and that the toy is a triangle. That way it is part of her everyday life by the time she starts to talk.
This is a great way to get her to know a "round ball":