Why? The Best Ever Question and Answer Book about Nature, Science and the World Around You by Catherine Ripley, illustrated by Scot Ritchie

From chapters.ca:
Everyday childhood activities, such as an excursion to the park, splashing in the bathtub, or fixing a snack in the kitchen, can prompt many questions from young children. Why is the sky blue? Why does my stomach g-r-r-owl? Why do cows moo? Curious kids want to know, and no adult has all the answers. Since 2001, Why? has taken over 100,000 young readers inside the kitchen and out to the park, from the farm to the supermarket, and from bath time to bedtime.

Ask me Anything: Every Fact You Ever Wanted to Know byKim Bryan, et al.

A question and answer book that answers a wide array of questions from all disciplines.

Why is Snot Green? by Glenn Murphy

From chapters.ca:
All the answers you will ever need! Why is snot is green? Do rabbits fart? What causes earthquakes? Do birds kiss? What is colour blindness? Why do we snore? Why do tigers have stripes? What makes our tummies rumble? Discover the answers to these and 192 other questions frequently asked at the Science Museum in this wonderfully funny and informative book. It is divided into five sections which cover everything from The Big Bang to bodily functions and cool gadgets.

One Million Things: A Visual Encyclopedia by Peter Chrisp

From chapters.ca:
Featuring gorgeous photographs that illustrate and educate, this visual encyclopedia is jam- packed with thousands and thousands of images that bring more than one million things to light.

A Really Short History of Nearly Everything by Bill Bryson

From chapters.ca:
Bill Bryson’s own fascination with science began with a battered old school book he had when he was about ten or eleven years old. It had an illustration that captivated him – a diagram showing Earth’s interior as it would look if you cut into it with a large knife and removed about a quarter of its bulk. The idea of lots of startled cars and people falling off the edge of that sudden cliff (and 4,000 miles is a pretty long way to fall) was what grabbed him in the beginning, but gradually his attention turned to what the picture was trying to teach him: namely that Earth’s interior is made up of several different layers of materials, and at the very centre is a glowing sphere of iron and nickel, as hot as the Sun’s surface, according to the caption. And he very clearly remembers thinking: "How do they know that?" Bill’s storytelling skill makes the "How?" and, just as importantly, the "Who?" of scientific discovery entertaining and accessible for all ages. He covers the wonder and mystery of time and space, the frequently bizarre and often obsessive scientists and the methods they used, and the mind- boggling fact that, somehow, the universe exists and against all odds, life came to be on this wondrous planet we call home.

Now You Know Big Book of Answers by Doug Lennox

From chapters.ca:
Doug Lennox is back with a treasure trove of his favourite trivia culled from his four previous Now You Know books plus 125 brand new questions answered by the master of Q & A. Lennox dispenses knowledge concisely, never losing sight of the joy and fun of discovering the why of ordinary things. He covers a wide range of topics from sports to war, from crime to religion, from pop culture to politics. Answers to questions and the origins of hundreds of expressions and customs are brought together in this fascinating compilation. Thanks to Doug, you'll learn the answers to:
Why do humans kiss?
Why is a miserly person called a "cheapskate"?
Why is an evil adversary called a "villain"?
Why is football played on a "gridiron" and a leg injury called a "charley horse"?
Why is confetti thrown at a wedding?
Why do golf courses have 18 holes?
Why do the British drive on the left and North Americans on the right?
Why is a road called a "highway" and the ocean the "high seas"?

Born Smart? Why Animals do What They Do by Peter Cook and Laura Suzuki

A comic book like book about animal instincts that is entertaining and interesting.

Transformed: How Everyday Things are Made by Bill Slavin

From chapters.ca:
CDs start out as sand. Blackboard chalk comes from tiny sea creatures. The objects all around us -- every single product in the world -- is made from elements found in nature. Discover how nature is transformed into more than sixty things we eat, drink, play with, wear or use every day. Technology changes constantly, but the stages raw materials go through to become finished objects remain much the same. On every page of this book, these processes are described and illustrated step by step. The text and artwork combine playfulness with encyclopedic attention to detail. This unique and fascinating book will inform and entertain every step of the way. Includes a glossary, index and further resources to help children, parents and teachers.

The New Way Things Work by David Macaulay

From chapters.ca:
Guided by a charming, but slow-witted woolly mammoth, readers are introduced to machinery in The New Way Things Work. Demystifying the computer age and leading readers into the 21st century - a world in which masses of information can be squeezed onto a single microchip - this updated edition includes more than 70 new pages of the latest developments. David Macaulay explains each scientific principle shedding light on today's intimidating, state-of-the-art technologies.