I have to respectfully disagree with Bubblehead. I've had the chance to try both the NED and Peapod and while the NED's hull dimensions are technically larger than the Peapod's, the hull shape actually makes the Peapod roomier. From the inside, it feels like a much larger boat.
Here's 2 pictures from CLC, each showing 3 occupants of a rowed boat.

The Peapod occupants can spread out all the way to the ends of the boat with no knees banging or dodging of oar handles.

Here, the NED's narrow pointy shape at the bow and stern push the crew closer together. If the one in the middle wasn't so petite there'd be some serious knee-banging. As it is, she's got to be on the alert for an accidental poke with the oar handles.
Another reason I'd rather carry a bunch of kids in the Peapod than the NED is the difference in stability. While the NED's sloping sides give it wonderful ultimate stability, the initial stability is not as great as the Peapod's. A herd of kids bouncing around in there will be making it wobble left and right while a Peapod will stay pretty much rock-solid.
Finally, there's the difference in freeboard. The Peapod has more of it so there's less chance of someone dropping something overboard. It also makes the boat more tolerant of overloading. The higher freeboard, along with the better initial stability, give the boat a better feeling of safety for inexperienced passengers. It's less likely to make a youngster feel insecure.
The Peapod is also an absolute joy to row. It's the best rowboat I've ever tried and I've been rowing since the first days of the Johnson presidency (Lyndon, not Andrew). I'd have no qualms about sending kids out in it on their own.
Both the NED and the Peapod are S&G lapstitch, neither is strip-built. They use essentially identical build methods so that shouldn't be an issue. The longer NED will require a larger workspace. I'd rather trailer either of them though the NED could be cartopped in a pinch with the right car and some help.
As for the kids getter bigger, when that happens just build them Eastport Prams. Start them out at 2 to a pram and keep adding to the fleet as they keep getting bigger.
Have fun,
Laszlo