Time Meddlers on the Nile — Deborah Jackson

One of Canada's top scientists has discovered the secret to time travel. But everything has gone wrong. Thirteen-year-old Matt Barnes and Sarah Sachs, while attempting to rescue Matt's father from multiple universes, face an even more challenging obstacle: the erasure of their own timeline. What can they do before they, themselves, are erased? Somewhere along the Nile the two teens must prevent the ultimate meddling during the time of Nubian pharaohs and princes, palaces and temples to rival the ancient Egyptians and fearsome desert raiders. They must puzzle out the moment and event where Matt's father or his arch nemesis, Nadine, interfered with history. If they don't, it could mean the end of time as we know it, or a never-ending loop of time.

 * Time Meddlers is Recommended in the Children's Literature Review and Canadian Teacher Magazine