This is what I am trying to say here, learning the koran would have been important to the mother, but not important enough that she would beat him to death.
That happened because she was unhinged, damaged or an abuser. As far as I understand it, learning the koran isnt important enough to muslims that they would beat their kids - it just doesn't have that status - not obeying or not achieving or not performing or conforming on the other hand possibly could.
I live in an inner city "ghetto" (!) type area as some might call it, my neighbours send their children to learn the koran, same as 1000s round the country, but they dont kill them, beat them and neither do the vast majority hit them either.
This poor boys death isnt about the mothers religious beliefs, if she had the same background, genes, upbringing etc but was a christian or hindu, she would still have beaten her child to death, but for a different reason.