Here's why:
* Common Features: These spellers were characterized by their focus on rote memorization of spelling words, often organized by grade level or subject. They typically included exercises, dictations, and sometimes even illustrations to help students learn.
* Popularity: They were popular teaching tools in the early 20th century, particularly in American schools.
* "Blue Back" Reference: The term "blue back" likely comes from the color of the cover of these books, which were often bound in a distinctive shade of blue.
It's important to note that while the term "blue back speller" is familiar, it's not a standardized or official term. The specific spelling book referred to as a "blue back speller" could vary depending on location and time period.
If you're interested in learning more about a specific "blue back speller," providing additional information, such as the author, publisher, or approximate date of publication, would be helpful.