I’ve been estimating things since I was a kid. Sometimes before a taking a trip, I would look at a tree in our yard. Then throughout the trip, I would try to estimate about how many leaves were on the tree. Of course, I could never find out the exact answer, but it gave me something think about during a long car trip. I would think of the tree (which probably helped me from feeling homesick, too) and adjust my estimate over and over again. I hope that my readers have fun looking at the pictures in these books and become more comfortable playing with big numbers.

Making these books is a real treat for me because I get to put the photos together. Well, most of them. Some of the photos, like the bunnies and the penguins, I buy from a photo service. But I arrange the photos of objects like cereal, cherries (they’re plastic!), and rubber cockroaches. Depending on the photo, I usually spend between one and four hours crawling around on the floor in the studio, setting things up. Then the photographers, Arnold Katz and his son Dave, light the set-up and take a very high resolution digital photo.

I love the quality of the digital photos, but I am pretty old-fashioned when it comes to the set-ups. For the cover of Greater Estimations, I envisioned an army of rubber ducks marching toward the reader. I think most people these days would have taken a picture of one duck and then used computer software to cut and paste the duck army. But I think you can usually tell when an artwork is made that way, and I prefer the real thing. So I bought all those ducks and set them up on a table. It took about five hours. (Of course, sometimes computer artwork does come in handy. I also wanted to include a picture of 10,000 ducks in Greater Estimations and there was no way I was going to buy that many ducks!)

Greater Estimations gives readers more chances to practice their estimating skills. It adds some new twists, like measuring length, weight, area, and volume. It also tackles some really big numbers, like the number of hairs on a cat or blades of grass on a football field. Buy most importantly, it includes a very cute picture of my dog, Aggie.