Why are they killing children in Nigeria?

We are continually being told that Islam is a peaceful religion, that Muslims are non violent, amicable people. Why then, are Muslims killing Muslim children in Nigeria? Apparently just because they are going to school! Are these killers worried that educated children will see them for what they are and won't want to join them in their cause, but just might want to go on to become teachers, doctors, nurses or some other worthwhile occupation? Yes, I can see why militant rebels would not want anyone to get an education.

Sticks and stones will break your bones and words CAN hurt you!

 “Sticks and stone may break my bones but words will never hurt me” - WRONG
As soon as I heard about Charlotte Dawson's death, I thought, OK here we go - now all the ugly trolls will come out to play, but I certainly did not expect the Rev. Fred Nile to be among them.
Obviously I did not know her personally, but she seemed like a nice, genuine person, who like 99.99% of the human race had some tough choices to make in her lifetime. However, it is NOT up to the righteous few to judge or condemn her for these choices, so Fred Nile, butt out! You sound like those fanatical religious nuts in America who disrupt funerals of fallen soldiers or stand on street corners proclaiming God hates everyone but them. There is nothing good, charitable or benevolent (all the things a good Christian is supposed to be) about people like this, and for all the good things you proclaim to do Mr Nile, it is all too easy to alienate people with ill chosen words.