This story serves as an object lesson about pets, love and loyalty. A good way to represent it on a bulletin board is to create a storyboard showing Mary leaving the house and walking down a road to the school with the little lamb following behind her. You can then show the teacher putting it outside the school and finally Mary coming outside and finding the lamb still there.
Hey Diddle, Diddle is a classic nursery rhyme that can be used to help children remember aspects of a story. Create a storyboard divided into quarters. In each section have a pasted on image of one of four characters performing some action. For example, you could show the dish and the spoon running in the first corner, the cat fiddling in the second, the dog laughing in the third and the cow jumping over the moon in the fourth. Then after reading the nursery rhyme, ask the child what each character is doing.
This one can serve as a lesson about safety. Have an image of Humpty Dumpty sitting on a very steep wall on your bulletin board. Below this have all the kings horses and men, as well as modern doctors and ambulances. After reading the story, ask the children what they think Humpty Dumpty did wrong and what would have been safer. Then talk with about other things that they should not do, like crossing a street without an adult or running with sharp objects.
Twinkle Twinkle Little Star can be a great way to start to teach children about space. Cover your bulletin board with black paper and paste stars and planets on it. Then put an image of a child looking up through a telescope at the bottom. After reading the story, you can talk about the stars, the moon and the planets (in a very basic way).