Here's a short description of Berry that I found on their web site:

"Berry was founded in 1902 by Martha Berry (1866-1942) as a school for enterprising rural boys when few public schools existed in Georgia. A girls' school was added in 1909. Berry became one of the nation's most successful educational experiments, combining academic study, student work and interdenominational Christian religious emphasis."

Do you think the owner of your book might not have been connected with Sharp at all? Maybe she heard students at Berry & made notes in the book of those that she also collected. Has she also, possibly noted differences in the versions?