I do not think you are a jerk. But I think you’ve gotten some good advice here, about how different people have different goals in social conversation. I, personally, think sitting around and comparing facts and sources is a good time. It took a long time for me to learn that a lot of other people who are not me find the greatest value in the conversational exchange itself.
Even when you said this:
*Let me ask this: If the situation were slightly reversed, and I had made the assertion that daddy long legs were not poisonous, someone disagreed with me, and I then pulled out my phone and proved my point… it seems to me that no one would consider that I was a jerk in that case. *
Actually, yes, depending on context, a lot of people might consider you a jerk in that case, because you harped on a point and wouldn’t let it drop instead of letting the conversation move on naturally. I would not be one of those people (I once had a five year argument with someone about copperhead snakes), and I think a lot of us on the SDMB like to have friends who enjoy doing some on-the-spot research about daddy long legs … BUT the world is full of other people, such as people in your family and coworkers and random acquaintances who place more value on being able to let things go and gracefully move on to something else.
Specifically let’s look at some other parenting-specific issues … because unlike coworkers, it would be fairly dramatic if you decided to stop socializing with your stepsons.
It really gave me pause when you described your younger stepson’s reaction to being questioned, after the report. Part of it is definitely that he’s 12. The other part could very well be that he was already apprehensive that you were going to be actively all up in his business about a school project that already happened … and you confirmed this anxiety with your behavior. I’m not surprised he was exasperated and defensive. It sounds like the main thing you are encouraging is for him to be wary of you, instead of encouraging good research habits. I’d be worried that you are doing more to make him hate research, rather than being excited by it.
With the fire pit conversation (and the point here is more about future conversations that are similar to the fire pit situation) here are some other paths you might have taken:
– as already suggested, let the kids try to out-research each other on Opiliones facts. HOWEVER, I will note that at 12 and 18, they will totally see through you if you try to fake them out into doing research. You have to really sit back and let this happen more organically.
– steer the conversation in a different direction, like “hey everyone, what is the biggest spider you personally have ever encountered?” Tall tales welcome. It was the size of my HEAD and it ATE a PUPPY.
– let it fall into a “to be continued” area, by saying something like “That episode of Mythbusters sounds interesting, let’s watch that together sometime.” and then MOVE ON to a new topic.