I think in most states Lizzie would HAVE to be embalmed. Tough luck, if she WAS alive at that point. It bugs the crap out of me that she has been talking for MONTHS about how they will think she is dead, but she won't be. Then, "Oh, she's dead, what a bummer." Never a mention of her obsession or the possibility that she could be not dead, it would appear that they didn't even get a second opinion! (And with Jooooliahh proclaming her dead, I think that would have been a decidedly good idea).
I think Roger is on a bender in London. No problems believing THAT part of the plot!
It may vary from state to state, but you do NOT need a teaching certificate to teach in a private school in either Arizona or Missouri. Some private schools have some education requirements, but that is up to them. You don't need a teaching certificate to be a substitute teacher in the public system here in Missouri also, though you do need some college, I think two years. My understanding was that Vicky grew up in the orphanage and then continued on a teacher there. Presumably, as a private school that would be fine. You don't need a teaching certificate to home school either, and that is essentially what they are doing with David and Amy. (Though was certainly not as common then, and would have been a whole 'nother enchilada than it is now.) Since David and Amy never actually have any lessons, I don't think it matters whether Naggie is qualified or not. Personally, I thought it odd that Naggie wanted to go back to work at the diner so bad after her kidnapping ordeal, but after her dad died and she probably needed to, she didn't.
My older son has watched the show with me in the past. My younger one is now. He was really interested in the children's actions today!