My son read a series of books in 4th grade in 1987-88, and we cannot remember the title or author. The books were about a young man and his friends who solved crimes, we believe. The word Brain was in the book title. There were 4 or 5 books in the series. It was not Hardy Boys or Nancy Drew. Can you help with the title?

Encyclopedia Brown?

"Brown" rather than "brain?"

Sammy and Brian Mystery Series by Author Ken Munro Or this?

There is series called the Great Brain by John Fitzgerald