I have bought several books in this series from Usbourne for my 5 year old son, and I think they are all brilliant. My son wants me to buy more for Christmas.
The books are neat in size, hard-backed, and full of clear colour diagrams and photographs for illustrations. The text is brief, simple but to the point, explaining huge facts in a way that is easy for young children to get their heads around.
If you want your child to take an interest in the world around them then take a look at all the books in the series. I have also purchased 'Weather', 'The Romans', and 'London', and my son loves all of them. If your child is also learning to read by themselves, then these are also suitable. There are one or two big words to deal with but if you have already read the book through with them, they will know this, and there is a dictionary at the back.