Here we are again, as the clown says in the circus! "Right you are, Pepper. And I'll be glad to get back to Putnam Hall once more," responded Major Jack Ruddy, as he followed his chum from the lake steamer to the Cedarville dock. "Hello, there is Andy!" cried Pepper Ditmore, as he caught sight of a familiar face in the crowd of cadets, "Andy, where have you been? Why didn't you come on the boat with us?" "I got in last night," answered Andy Snow. "How are you, anyway?" And he shook hands cordially.
So choked with "boys' adventure" story tropes I kept literally facepalming. I suppose it's okay if you like that kind of thing, but as a mystery it's no mystery at all - I had it solved correctly the moment a certain character turned up in the book; as a school story it's lamentably short on detail related not to the boys but to the actual school, which appears to have just four teachers for a boarding school with nearly ninety pupils, and its teachers almost beneath mention...
Quite honestly, it's only worth reading if you happen to be a Stratemeyer Syndicate completist (Nancy Drew et al), and perhaps not even then. I gave it two stars instead of only one because it is a clearly-plotted story that hangs together without too much gratuitous content and doesn't read badly, and the characters' personalities are fairly consistent throughout. I don't, however, plan ever to read it again.
Interesting... But NOT as good as the Rover Boys series. It was interesting to find out who did what but... It took a while to get into to the real mystery. It is not as adventure filled as the continuing series, the Rover Boys.