Children's Books For Philip (and other desperate parents with young readers)

Edited to add: the quality and general acceptability of these books varies wildly. They do, however, share one quality: they were written before the advent of the cellphone. 

Mystery Book Series I've Read (not claiming they have literary merit)

• Magic Tree House
• Cam Jansen
• Jigsaw Jones
• Percy Jackson
• Little House (and ancestors)
• American Girl Series (original 10 dolls)
•  The Magic Attic
• Roald Dahl (some are mysteries)
• Mercy Mayer
• Madeleine L'Engle (some are kids books/mysteries)
• Pippi Longstocking
• Bobsey Twins 
• Trixie Belden
• Barney Mysteries (Enid Blyton- highly recommended!)
• Mandie Books (evangelical Christian)
• Bill Myers - Bloodhound Inc. (evangelical Christian)
• Cooper Kids Adventures (evangelical Christian)

Other Book Series (Mystery and Not) Read by Me/Suggested by Family

• Arnold Lobel
• Three Investigators
• George Selden
•  Sorche Nic Leodhas
• Judy Blume 
• Crockett Johnson
• Mary Norton
• E.B. White
• Betty MacDonald
• Gen Zion
• Rev. W. Audry
•  G. A. Henty
• Beverly Cleary
• Library Award Winners (Mom: "These tend to be for girls")
• How to Train Your Dragon
• The Hobbit
• "Redacted Tom Clancy" (Mom)
• Sherlock Holmes Short Stories
• Harry Collingwood