A suggestion passed along by my friend Sarah B., quoted here with her permission:

“Anthony at teacher’s edition had a great idea for our timeline. We bought strips of brightly coloured paper which allowed us to make a comparative time line of ancient history for the different continents – yellow was Asia, Blue was Europe, Red was Africa etc which allowed us to see really clearly what was going on in the other continents when the pyramids were being build in Egypt, for example. It really helped clarify things for me because obviously we tend to learn in a linear way – Sumer then Egypt then Greece etc etc, but this really allowed us to see the way the whole world was developing at any given time.

“And it’s a lovely bright addition to our wall.”

Here’s a site that sells printable timeline figures—my kids love exploring the CD-rom, hunting for their heroes.