John Sobol confirmed his father's death to The Washington Post.
The elder Sobol worked for the New York Sun and Long Island Daily Press before going on to write more than 60 children's books. His popular "Encyclopedia Brown" mysteries, which followed the adventures of the titular boy detective, sold tens of millions of copies worldwide and were credited with getting even reluctant young readers to open a book, the Post said.
He is survived by his wife of 56 years, Rose Tiplitz Sobol, of South Miami; three children, Diane Sobol of Coral Gables, Fla., Eric Sobol of Sarasota, Fla., and John Sobol of Berkeley Heights, N.J.; his sister; and four grandchildren. His son, Glenn Sobol, died in 1983, the Post said.