I was going to say that the howlers you see like that would fill a book - but they already have, haven't they?! That Lynn Truss 'Eats Shoots and Leaves Thing' which should be standard text material at all schools, I reckon!
I'm paranoid about spelling and grammar, but that's just me - the way children are taught these days, it's very much more about stimulating the creative flow, rather than bogging them down with pedantic rules and syntax, but having said that, they do still have spelling lessons, at least my two do.
-------------------- "The fragrance always stays in the hand that gives the rose."