You can also try Little Monsters Detectives, now on Kickstarter (12 days to go!!!), the English speaking version of Pequeños Detectives de Monstruos.
It is very popular in Spain and France!
Also, from the same writers and game editorial,Los Buscaduendes for a little more grow up group of children
And, because the same editorial has found that kids love to roleplay: Magissa. This one more close to the classic Fantasy RPG style.
