About 1500 BC, new rulers unified Egypt again as the New Kingdom. At first, their sculptures and paintings were not much different from the sculptures and paintings of the Middle Kingdom that came before. As before, Egyptian art was a lot like the art of other African artists, but mixed with ideas from West Asia. In the 1300s BC, though, the New Kingdom pharaohs developed a new art style we call the Amarna style. Amarna style sculptures and paintings were much more abstract, less real-looking than before, and sometimes really exaggerated – in many ways, more African and less West Asian.
After Amarna, around 1200 BC, Ramses and his successors brought in new interests to art, where the main idea was to be very big and impressive, even if the details were not so fine. Reliefs are cut into the stone, instead of the background being cut away as they were in Old Kingdom art.
New Kingdom artists, and their audiences, liked a loose, enthusiastic style, more than the old tightness and precision. And, because the Egyptians were doing a lot of conquering at this time, the reliefs often show wars or prisoners.
But with the collapse of the New Kingdom into the Third Intermediate Period about 1200-1100 BC, Egypt became a much poorer country. Nobody in Egypt was rich enough anymore to pay for temples and giant sculptures, and hardly any were done. Artists and sculptors moved to other, richer countries like Assyria where they could find work.
Eyewitness: Ancient Egypt, by George Hart. Easy reading.
Ancient Egyptian Art, by Susie Hodge (1998). Shows kids how Egyptian art relates to Egyptian religion and culture.
Hands-On Ancient People, Volume 1: Art Activities about Mesopotamia, Egypt, and Islam,by Yvonne Merrill and Mary Simpson. Art projects for kids, though the directions are really aimed at teachers or parents.
The Art and Architecture of Ancient Egypt (Yale University Press Pelican History of Art), by William Stevenson Smith and William Kelly Simpson (revised edition 1999). The standard for college courses.
Egyptian Art, by Cyril Aldred (1985). Another standard.