The other day I was watching a documentary with him and I got bored after about a half hour, so I went to the bathroom hoping he would keep watching it. I came out of the bathroom, and there he was standing there in the hallway. He said "I paused it. So are you ready to finish it now?" Sighing, I went back to watch the rest of it with him even though I really wanted to just curl up in bed with a silly novel. Or make dinner.
I may sound like a horrible parent here, but I honestly believe it's ok to not share our children's every interest, and to not have to sit through long videos we're not really that interested in! My teenage dd, for instance, loves to sing. She'd sing for me all day if she could, and that would drive me nuts. She has a beautiful voice, she's taking voice lessons, she's discovering she has a beautiful voice, but I still can't think straight when I'm listening to her sing. Same thing with ds who plays keyboard and composes. He loves loves loves to share his music, but with both of them, I will tell them if it's not a good time for me to listen, and I had to learn how to do that without feeling guilt over it

Blackcat, it's clear you are a caring and adoring parent... your ds will survive if you don't follow him down every niche and cranny of every history topic he becomes obsessed with! Let him know you love how he loves to learn, but he won't think you him any less if you acknowledge that loving him doesn't require you to love the details of the Crimean War

It will also be ok when he's doing math that you don't know how to do. Or speaking Spanish 5 years ahead of wherever you left off in school etc. The important thing is to enjoy your time with him, even though it might mean finding a middle ground that isn't always his first choice.
I don't know if the teacher is even aware that he is like a walking encyclopedia and that he surpasses most adults in terms of knowledge in some areas. I will bring it up at conferences, but I don't know what they would do anyway. They can accelerate him in math, but what about social studies and history?
JMO, but the thing about studying social studies and history isn't so much memorizing all the details as it is contemplating the complexity of it all, making connections, sometimes just reading and enjoying it. The deep thinking, across the board, was a challenge for our ds in elementary school because it just didn't happen in classroom conversations. What helped the most was moving him to a classroom (which for him was in a different school) where there was a higher population of higher-IQ kids and also the overall curriculum was one year ahead of the public school. The teachers can also make a *huge* difference, depending on how they teach and what they expect the children to do with the facts that are taught (i.e., are the teachers just shoveling facts in and expecting memorization, or are they encouraging students to think at whatever level they are at?).
Anyway, as you know, my ds is 2e also. Moving him to a more advanced curriculum wasn't an issue due to 2e - the issues with 2e have always been tied to teacher willingness to allow accommodations and to accept that ds has a 2nd e and not mixing up behaviors related to the 2nd e with laziness or lack of motivation. Those issues can arise in *any* level of classroom. On the flip side, ds always worked better in an accelerated classroom - his challenges didn't go away, but he had his intellectual strengths met in a more meaningful way, so he was happier overall.
Best wishes,
polarbear