My seven year old son is currently very curious about big numbers. He is interested in the number of seconds in a day, 86,400, the number of minutes in a year, 525,600, and the number of stars in the Milky Way, estimated at around 300 million. Such big numbers certainly drive his curiosity.
His older sisters on the other hand, have grown out of being impressed by magnitude. At ages 8 and 11 they already comprehend that there is not a number bigger than all the rest. They don’t get overly excited when they hear about a million, a billion, a trillion or even a quadrillion. This is 10 to the power 15 by the way; a thousand trillion or a million billion.