Value of The Children's Encyclopedia?

I have a set of The Children's encyclopaedia edited by Arthur Mee, published by the Educational Book Company, and copyrighted in the USA. There are 8 volumes, in very good condition. I believe it is from sometime between 1920 to 1930 as the illustrations are of that period. Are they of any value, as I want to put them into auction? I also have 8 volumes of The New World of Today, published 1921, excellent condition, by A R Hope Moncreiff, published by The Gresham Publishing Company, LTD.

By David