Students across Australia gathered at the same time on the same day to read a chosen Australian picture book as part of the the Australian Library and Information Association event.

This year's book, The Cow Tripped Over the Moon, was a hit.

Some lay on their bellies or lounged on pillows, while others sat cross-legged with chests puffed out proudly at Communities@Work's Abacus Child Care and Education Centre in the Treasury Building.

But all were entranced as the spouse of the Governor-General shared the humorous story of perseverance based on the Hey diddle diddle nursery rhyme.

Lady Cosgrove said the group story was her first reading of the book by Tony Wilson and Laura Wood.

"I loved it," she said. "I thought a lot of the failed attempts at the cow jumping the moon was very entertaining for children."

Abacus Childcare manager Melita Pendergast agreed, saying the message to keep trying despite set-backs is important to instil in youngsters.

She said storytelling, particularly rhyme, delivered huge benefits for early literacy.

After Lady Cosgrove had read the picture book , the children recited the traditional rhyme out loud in unison.

"Rhyme is really important I think they say children who know four rhymes off by heart by the time they are four years old are among the best readers," Ms Pendergast said.

"Literacy is really important to early development. Listening to different words is really good for them, as well as the rhyme, the repetition, the patterns and sequencing."

Many of the three to five year old may not have fully appreciated who their VIP guest was, however staff at the centred were honoured she gave up time in her busy schedule to spend with the children.

While she has grandchildren of her own, Lady Cosgrove said it wasn't often she had the chance to relish reading a picture book with a group of eager young learners.

"Coming to do anything with children, read a story or visit schools, it's just amazing - very relaxing," she said.