Set of Six (6) I Wonder Why Books

This is a set of six I Wonder Why books published by Southwestern Company by arrangement with Kingfisher Publications.  Original editions were printed in 1997 and these books were reprinted in 200.
The books measure 9 1/4 " x 11 1/4", they are hardcover, very attractive illustrations on each page help to explain and answer the questions on each page. Like new condition.  It appears that the books were hardly used.  Spines are very straight and no bending.  Some of the books seem to have been opened only a couple of times.  No marks or smudges. 

Books are as follows:

I Wonder Why Trees Have Leaves and other questions about plants 31 pp plus index
I Wonder Why Pyramids Were Built and other questions about Ancient Egypt 31 pp plus index
I Wonder Why Camels Have Humps and other questions about animals 31 pp plus index
I Wonder Why Triceratops Had Horns and other questions about dinosaurs 31 pp plus index
I Wonder Why The Sun Rises and other questions about Time and Seasons 31 pp plus index
I Wonder Why Soap Bubbles and other questions about Science 31 pp plus index

Example of contents - I Wonder Why Trees Have Leaves
  What is a plant?   Where do plants grow?  Are plants really alive?  Why do trees have leaves?  Why do some trees lose their leaves in the fall?  Why do leaves change their color in the fall?  Why do roots grow so long?  Why are stems so straight?  Which plants grow in water?  Which are the smallest plants?  Which forests grow in the sea?  Which plant..traps a treat?...fools a fly?....snares a snack?  Why do plants have flowers?  Which flower fools a bee?  Which is the smelliest flower?  Why is fruit so sweet and juicy?  Which plant shoots from the hip?  Which seeds sail away?  Which fruit gets forgotten?  When does a seed begin to grow?  Do all plants grow from seed?  Which plant grows the fastest?  Are fungi plants?  What puffs out of a puffball?  Which are the oldest plants?  Why do trees have thorns?  Why do stinging nettles sting?  Which plants look like pebbles?  Which plants get a lift to the light?  Which plant has a private pool?  Which plants strangle and squeeze?  Can plants grow in a desert?  Can you pick fruit in the desert?  Can you find flowers in the desert?  Which are the tastiest plants?  Why do carrot plants grow carrots?  Do people ever eat grass?  What are 300 million year old plants good for?  What are plants good for today?  Index.

Although the bright illustrations will be attractive to younger readers, they are mature enough to appeal to any child.  Lots of answers for the most inquisitive child.  A great way to introduce nature and science as a hobby, interest or part of beginning home schooling.