A thumbs up for the entire Percy Jackson series! I’ve added the classic Mythology by Edith Hamilton which I read and loved as a child. You may as well capitalize on an interest in Greek Mythology and even Roman Mythology that this series will instill in your child. The Usborne is great for younger readers but Edith Hamilton is THE expert and her Mythology book has greater detail.
If you want a great old-fashioned fairy book and tire of those repetitive Rainbow Fairies, try No Flying in the House by Betty Brock.
Grace Lin is the Amy Tan of Children’s Literature. Her latest book, Where the Mountain Meets the Moon, is her best yet. Perfect for 2nd-5th graders or even older. She weaves Chinese folk tales into a tapestry of stories where the whole is much greater than the sum of its parts.