She was learning Naq technology since she was 2? 
Things she can’t discuss with a 12 year old, Merrin.
Reversing the polarity always works. 
Cool effect on the generator coming online.
Like he said, his son was in his head. THat was just the body of his son.
Jack’s a sneaky bastard when he wants to be. I wonder if he thought this through all the way to its logical conclusion.
This was Cassie’s elementary teacher? Nice nod to continuity.
Didn’t remember her first painting.
I think the Nanites give that race something like hive mind. They don’t have knowledge of each other’s current state like the Borg do, but they all get a shot of identical knowledge at the same time.
Wouldn’t the other students be a bit curious about Merrin?
You know, this didn’t really teach her about conventional learning if she’s only there for art.
I think he thinks that he’ll convince Marrin to stay, but he doesn’t understand that she knows that what she knows is important to her people and that she needs to go back.
And her funny stories of the planet that she came from and the creepy old guy that is sitting next to her in art class… 
Remember, they were happy to see Jack. Sounded like he stopped by every once in a while.
This is what I was referring to. Do you think he realized that if she went back, her nanites would show them how to teach?
Forgot how cute the ending was.
The school might have kids that are refugees from other worlds. And back to Jack being known at the school, I used to be a student teacher, and adults that are not part of the school staff or parents of a student are NOT welcome on school grounds. There are a few ways that he might be know to the students, but when would he have the time to regularly interact with Middle school students?
As for the second question, I think he was trying to convince her to stay and not go through the procedure.
Colorado Springs probably has a lot of children of military personnel, and Jack seems to be pretty good with kids in general, so I could see him knowing some of them from that.
Starting up 306 now.
My guess is Writer’s fiat, to show that Jack is a likable person and good with kids and they didn’t bother with a backstory to say that he was a Little League coach or school volunteer of some kind.
Sorry, I used to work in that environment, training says “Creepy old guy- call cops” not, Friend of children, let him hang out in art class.
All that’s missing is the Ark of the Covenant.