The Last Timekeepers and the Arch of Atlantis

Children are the key to our future. And now, they are the only hope for our past.
When 13-year-old Amanda Sault and her classmates land themselves in hot water after a cafeteria food fight, they're assigned to yard duty as punishment. After the kids uncover a mysterious stone arch hidden in the overgrown backyard owned by the Witch of White Pines, they learn that it's an ancient portal created by the lost civilization of Atlantis.
Chosen by an Atlantean Magus, Amanda and her reluctant companions are swept into the secret world of the Timekeepers: legendary guardians entrusted with preserving history from a sinister force known as Belial. Their first mission? Travel back to 13th-century England to ensure a young Robin Hood fulfills his legendary fate.
But time travel comes with strict rules, and one wrong move could rewrite the past... and erase the future.
Packed with high-stakes adventure and a touch of ancient magic, THE LAST TIMEKEEPERS AND THE ARCH OF ATLANTIS is the first book in Sharon Ledwith's series of novels for middle grade readers and adults alike.