If you enjoyed Spider Kane and the Mystery Under the May-Apple, you may enjoy reading some of the following books:
The Secret of Wildcat Swamp by Franklin W. Dixon.
An archaeological expedition in the West turns into a desperate attempt to capture robbers and an escaped convict.
The Flickering Torch Mystery, by Franklin W. Dixon.
When two suspicious plane accidents occur near an eastern airport, the two Hardy brothers investigate the case and find themselves in greater danger than they anticipated.
Cam Jansen and the mystery of the monster movie / David A. Adler.
A fifth-grader uses her photographic memory, her mother, and her friend Eric to find a missing reel of a monster film they go to see.
Encyclopedia Brown and the case of the treasure hunt / Donald J. Sobol.
America's Sherlock Holmes in sneakers continues his war on crime in ten more cases, the solutions to which are found in the back of the book.
Super sleuth : mini-mysteries for you to solve / Falcon Travis.
Describes forty-three crime puzzles, which the reader tries to solve
with the aid of clues, codes, alibis, and other evidence.
The Absent Author / by Ron Roy.
Dink Duncan and his two friends investigate the apparent kidnapping of famous mystery author Wallis Wallace.
The Franklin W. Dixon books are Hardy Boys mysteries and the book by Ron Roy is part of the A-Z Mysteries series. Most of the books I've
included in this list are part of a series, so if you like them you can find others with the same characters.