I did nsw to nt with a 5yr old a 3 yr old and a newborn. So a little different in age, we had a travel box for the older 2 filled with masks (to colour) sticker notepads, books, colouring pages, crayons and pencils some sensory toys like the squishy things (technical name right there lol) and bubbles the box fit comfortably on their laps or on the floor at their feet. We also had DVDs and bop it the game the kids really weren't interested in DVDs or bop it unless it got dark. It was their travel box all the way 3 days solid in the car and it was the best!
I've done NSW-WA a few times now. With & without a DVD player - I definitely prefer with! - with new movies they haven't seen yet, so they didn't get too bored. Colouring books & pencils, diaries for the older girls to write where we'd been & what we'd seen that day (5-6 day trip with 1 driver). I loaded up on apps/games on my ipod & phone too.
I used the pocket things you hang on the back of the front seats, so everything was in reach. Plenty still ended up on the floor, but it makes life easier. Mine also collected bits & pieces at different stops too. Sometimes just a rock, or stick... or a lizard spine :/ but that gave them something to play with til the next stop. We left the 'booby book' at the rest area it was found at though...
Its very different crossing a desert though, the more to entertain them the better!
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