Well, yeah, but before the interw3bz and new-school MTV devolved the youth of the population into degenerate gibbering gimps, kids were able to be given a little more credit. I don't think it's unrealistic at all for a 13 year old Jake to know the occasional general model names of U.S. military tanks and aircraft carrier classes, or for Rachel to recognize the face of an international leader she saw on TV, or for Tobias to know a good deal about dinosaurs.
That would be more rare these days, but if we're assuming these books took place in the time frame they were published, it's not a big deal.