These hypothetical grandchildren will be sent some Nietzsche early on (13-14 yrs). Anyway, they should be able to stand as individuals at some point, decide for themselves.
I'm all for teaching children how to think critically for themselves, and not believe anything just because some authority figure tells them "this is as it is".
That's one of the reasons our nation is so screwed up. First the little kiddies are taught about Santa Claus, the Tooth Fairy, the Easter Bunny, then later it's Allah, Jehovah, Holy Ghost, Joseph Smith, Jesus, Krishna, or Hashem. At some point, it's Big Brother, George Washington and his Cherry Tree (but no mention of the Constitution), Abraham Lincoln and what a demi-god he was, how the we are to obey the authorities as Romans 13 tells us, and to always trust your doctor and don't ask him what that stuff is he's about to inject into you.
It's not just schools, preachers, and parents... it's the whole "dumbing down" system that has brought us to where we are. If I ever were to have kids (it's a little late for me now), the first thing I would teach them is TRUST NOBODY! Don't believe them. Don't believe TV. Research everything yourself, apply logic and common sense, make up your own mind and live the best life you can, and always strive to educate YOURSELF! Keep asking "why?"
And yes, that would apply to me as well. Don't trust me. I'd be the first to tell the kid that I am not sure about God, afterlife, etc. I would teach them how to learn stuff on their own, experiment with thought/reality exercises (no, not drugs) and use their own brain to determine what is true and what is right.
As to morals, I would teach the premise of compassion. But I would show them the benefits of being compassionate and not threaten them with hellfire if they are bad.
If I were to ever catch a teacher or some other "authority figure" adult teaching my kid "there is no God" or "there is a God", or "you'll burn in hell if you don't believe right", or "you are going to be worm food when you die" as though any of these propositions were fact, and do so to the point that the kid starts to lose his sense of reasoning for himself, well that "teacher" would sure catch hell from me.