The Boy Fortune Hunters series was the last hurrah for the Sam Steele books. The series must have been moderately successful, as more titles were added, leading to a total of six. L. Frank Baum was given the new pseudonym of Floyd Akers, but the stories still dealt with Sam Steele and his adventures.
The books went through two color schemes for their covers. The first titles were monochromatic, printed in black, white and tan on brown cloth. As the series continued, the covers were changed and became more colorful with red and green.
These are enjoyable stories, as are the Edith Van Dyne titles, and other teen titles Baum wrote. They are very much of their time period, and sometimes contain stereotypes and language that would not be considered acceptable today. But I do have to wonder, how many things are accepted and written for children today that would shock a turn of the century author!