"This holds the mana of both of those people. So it's not just wearing something, it's wearing the spirit of Beeby and Whiting as well."
Cowley's husband and four children attended the ceremony to support her.
She has written more than 1000 reading books to assist in teaching reading skills to schoolchildren.
Cowley said reading must have meaning for the age and development stage children are at.
"We can teach children to read and to hate reading at the same time if the process is dull and difficult."
She said her first duty as a writer was to entertain.
"Into the entertainment I built the skills, they're there, but a book has to be fun, it has to be enjoyable. Adults don't read dull and difficult material by choice, why do we expect that of children?"
She has written 41 children's picture books and has emphasised the need for children to see themselves in the books they read, particularly in their early years.
Her books are internationally renowned and used in more than 70% of American schools.
Cowley said the best book was always the last one because the writer was most involved in it.
"After a while I'm not a very good mother for my books. After I have given birth to them I tend to move on to something else but there are some books that I still like. One of my favourites would be Chicken Feathers."