Sarah Josepha Hale's rhyme tells a small, real story rather than just chanting nonsense syllables, which gives a one-year-old something to follow: a lamb, a school, a rule broken, a teacher's kind explanation at the end. The steady, singable metre makes it easy to repeat back.
Sung to its own tune, one of the first every child knows.
From Mother Goose / Nursery Rhymes (traditional). See the whole collection.
Mary had a little lamb with fleece as white as snow,
And everywhere that Mary went the lamb was sure to go.
It followed her to school one day, that was against the rule.
It made the children laugh and play, to see a lamb at school.
And so the teacher turned it out, but still it lingered near,
And waited patiently about till Mary did appear.
"Why does the lamb love Mary so," the eager children cry,
"Why, Mary loves the lamb, you know!" the teacher did reply.
About this poem
Written by Sarah Josepha Hale, 1830 · Roud 7622
This has an author too. Sarah Josepha Hale, an American writer and editor, published it in 1830. A well-loved story says the real Mary was a girl named Mary Sawyer who brought her pet lamb to school in Massachusetts, and that someone else wrote the opening lines. Hale said all her life that she wrote the whole poem herself, and the evidence sits with her. It is best treated as her invention, not a true event tidied into verse.
A good first story for a child, since it runs start to finish: the lamb follows Mary, causes a stir, is sent out, and waits. Walk two fingers along to show it trailing behind her. It suits a calm moment more than a rowdy one. Ask why the lamb loves Mary, and let the child answer before the last verse does.
Public domain. Text from The Little Mother Goose (illustrated by Jessie Willcox Smith, 1912), via Project Gutenberg. View the source edition