Kindaichi Shounen no Jikenbo Movie 1: Operazakan - Aratanaru Satsujin

Both series provide an unlikely hero doing the work of an adult and surprising all those involved. Also, Kindaichi, like Detective Conan (Case Closed), has a certain amount of comic relief incorporated into it. Anyone who loves Conan will enjoy The Kindaichi Case Files. 

A group of young people join the elite Detective Academy and just like Kindaichi help in cases when the police is helpless. The mysteries are really intriguing.  

If you love mysteries probably you will like this 39 episodes long series. It is about young girl called Maybelle West who happens to be miss Marple's niece and Mr Poirot assistant. Together they solve criminal cases and help to catch the culprits.