Wow, it never ceases to amaze me how many excellent conversations this book initiates. As you're reading, make sure not to be too rushed. Let your kids ask their questions, and look up the answers (even if you know them yourself). If you load the Wikipedia page, for example, even as you answer your kids' questions, they will get to see a few images and perhaps you will even learn a thing or two. I have included a few such images and links in this post that my kids asked questions about, so keep it handy as you read through Chapter 13. The examples below, however are just examples. Pay close attention to what your kids seem interested in and don't worry if you only end up reading one paragraph and spend the rest of the time researching and answering their questions!
Making a Submarine
"How do you make a submarine?" My 7.6 year old immediately started answering this question himself with, "well, just put a cover on a boat." Then caught himself with "and make sure it's watertight". His second best option for creating a submarine involved getting a twisty shell (I think he was imagining the Nautilus's namesake that we learned about in Chapter 10), capping it off (similar to the operculum we learned about in Chapter 11), then shrinking oneself down small enough to get into the shell. He asked if shrink rays actually existed, and didn't believe me when I said they didn't, yet.
The next question was what a helmsman was. I was surprised to find out that even a person who steers a spacecraft is considered a helmsman:
We have been hearing the word "frigate" throughout the story, but got a little confused here about which boat the characters were talking about, so we decided to look it up for good measure.
The biggest line of consecutive questions came at the end of the chapter (likely my kids were realizing that they could extend their bedtime slightly by asking more questions) when the Professor and Captain Nemo were discussing how much the Nautilus cost. Captain Nemo estimated the Nautilus cost 5,000,000 francs (including all the art and collections) but when you read this, make sure to remind your kids that due to inflation, in todays francs that would likely be closer to 100,000,000 (the math isn't very accurate here, but might be within an order of magnitude or so). In fact, the inaccuracies in this eventually led to a discussion on the price of gold, but first, the franc.
"Francs" were french money like dollars are Canadian money. These days, Switzerland uses Swiss Francs, but France has switched to the Euro.
"What is a Euro?" Well at some point (2002) a whole bunch of the countries in Europe changed their money over to the Euro instead of their individual currencies so that it would be easier to trade and travel between them.
"What type of money did Canada use a long time ago?" In the heat of the moment, and given that we were now pushing bed time every minute that I continued to talk, I jokingly said "beaver pelts", which interested my 9 year old. He said, well that would be great because then instead of spending $300 at the grocery store, we could just get a rare item and trade that for food. I then explained that that's how it used to be done. In a way you could do that even today, just sell the item for $300, then bring the $300 to the store. But where would you get the expensive item?
That discussion led us back to the idea of gold as a store of wealth. I suggested that gold is commonly used because it is more stable and could still potentially be used even if another currency crashes. I had to correct myself when I looked up the history of gold prices and saw this insanely volatile graph (and this only goes back to 1915):
Somehow this led to a discussion of what debt was, then mortgages and interest, but that had to be cut short because they were now late for bed!
Again, these are just examples of topics you might discuss, but keep the general process in mind as you're reading this book (or any book). I still frequently get the urge to tell my kids to stop interrupting and just listen to the book, but in many cases it's probably better to indulge them and have a side discussion. Yes, it will take far longer to get through the book, but why not further maximize their learning by having a few awesome side discussions?