Usborne Internet-Linked history books are packaged in a few different ways. You can purchase individual books: Prehistoric World, Ancient World, Medieval World, and The Last 500 Years. Or you can purchase one large book that combines all four books: The Usborne Internet-Linked Encyclopedia of World History. Usborne updates these books periodically, not changing the essential content as far as I can tell, apart from the most current events. These books include internet links, but those links are to a site which then directs you to the correct and current link. This means you don't have to worry about links being out of date.
These beautifully-illustrated history books can be used to cover the entire scope of world history. The target audience is approximately grades four through six, but older and younger children will likely also find them interesting. History and culture are combined as is appropriate for these grade levels. Although the text is broken up by illustrations, it flows in columns, making it fairly easy to read. Illustrations all have helpful descriptions—children are likely to browse through these books just “reading” illustrations and their descriptions. Timelines running across the bottom of most pages in Ancient World and Medieval World are helpful. Coverage in all books is necessarily spotty, but these books should give children a general introduction to world history.
The Prehistoric World is almost entirely based upon evolutionary assumptions, much of which is presented as fact. Ancient World begins with the first farming communities. It briefly touches on a few examples of ancient towns then moves on to the Sumerian and Egyptian civilizations. Hittites, Canaanites, Phoenicians, Assyrians, Hebrews, and other ancient civilizations also get brief coverage. Coverage of ancient Greece and Rome is given more space, and China, Japan, Africa, India, and the Americas also get attention.
Medieval World picks up where Ancient World leaves off, around 500 A.D. It begins with the Byzantine Empire, skipping over barbarian invasions to discuss the barbarian kingdoms that arose. Arabs and Islam, Vikings, Anglo-Saxon England, Charlemagne, and the Holy Roman Empire typify the range of topics covered next. Castles, towns, trade, and the Church all receive attention as significant historical factors. Coverage expands beyond western civilization to worldwide, including the rise of the Russians, conquest of North Africa, East Africa, Southern India, Southeast Asia, Pacific Islanders, the Americas, and other civilizations up through about 1400 A.D.
The Last 500 Years condenses a huge amount of history with selective and brief coverage. It begins with world explorations and closes at the end of the twentieth century.
These books should work best as spine books or as part of unit studies or other encompassing program to provide more context and understanding of the information. This is especially true if you plan to focus on only one time period for the school year; you would not have adequate material in any one of the smaller books. The internet links within the books might provide some of the added material you need. These sometimes appear in very small type at the top of pages, and sometimes there are a few pages dedicated to annotated lists of internet links.
The books are written from a secular perspective. Religion of any type receives relatively brief attention. Those teaching from a biblical Christian worldview are most likely to have trouble with The Prehistoric World and might skip it altogether.