Interesting and fairly simple history of the attempts to translate Egyptian hieroglyphics, and most notably the work performed by many scholars in trying to understand the text inscribed on the Rosetta Stone in hieroglyphics, demotic (a more modern form of Egyptian writing) and Greek. Because the same text was written in these three languages, the Rosetta Stone truly became the "Key to Ancient Egypt" in that it allowed the modern world to unlock the mysteries of Ancient Egypt through the hieroglyphic writing (of which numerous texts have survived on monuments, tombs, etc. for thousands of years).
The study of Ancient Egypt seems to be of great interest to children. I imagine that this is largely due to the pyramids (and other monuments) and the large quantity of strange and colorful artifacts that exist. A good study of this subject can lead to a greater understanding of how we learn about the past, the purpose and workings of archaeology and the "theatre" in which God chose to perform his spectacular display of signs and wonders which culminated in the Exodus of the Israelites from Egypt.
This book could play a useful role in such a study by explaining how modern man has come to learn about Egypt as well as presenting an introduction to how hieroglyphics work (another topic which children seem to be fascinated by).
Illustrations include sketches of Egyptian scenes dating form the 18th and 19th centuries (A.D.), black and white photos of Egyptian artifacts, and simple reproductions of hieroglyphs being discussed. The text includes a translation of the Rosetta Stone. Reading level is approximately 4th grade and up (could also be read-aloud to younger children).