Jason Chin: Hi my name's Jason Chin, and I'm the author and illustrator of Grand Canyon. Whenever I write a book about a place, I always visit that place to see it and to do research before I make the book. One of the really exciting things about going to a place is, when I'm there sometimes I make interesting discoveries that I would never of known about or never seen if I were just staying home and reading about the place and looking at pictures of it. So it's really important for me to go on location. So for Grand Canyon, of course, I went to visit the Grand Canyon and on the hike down into the canyon, I looked down at the side of the trail. And right there on the side of the trail was a fossil. And that just made me so excited. I never found a fossil before on my own. I've seen them in museums, but there's something about that thrill of discovery that was so special.

I called to my friends that I was hiking with, I was hiking with a group of friends and family, and I called them over. And I said, "Hey everybody I found this fossil, isn't this amazing?" And they all looked at it with these kind of blank stares on their faces because it was just about the most boring fossil that you could imagine. It was the borrow of a worm-like organism. It was about half an inch long, it just kind of looked like a little inch worm just sticking out of a rock. But then I explained to them that this fossil was 515 million years old, and was one of the first worm-like organisms ever on the face of the Earth.

So in my book, Grand Canyon, I had the character going back and forth through time. And the way that she goes back and forth through time is that she finds fossils and rocks, and she finds the fossil and it transports her to the past. The fossils are windows to the past. In the book what I did, was I put a die cut, which is a hole in the page. So on one page the character is walking through the canyon and she looks down and sees the fossil. And what she sees is the fossil, but what you see, as the reader, is that that fossil is actually showing through from the next page. 'Cause it's showing through the hole in the page where she is. When you turn the page, she's been transported to the past and what had been a fossil showing through is now the living organism. So the living organism was showing through as the fossil.