A storm destroys a historic oak tree at the elementary school. Two fifth graders, Sebastian and Sara explore the ruins of the tree and are transported into a world unseen to humans for centuries. This world is full of elves, mermaids, gnomes, and magic. The children become swept up in a centuries-long battle between elves and evil spirits called Kylo, which now threaten the human world if they are not stopped.
The Grotto Under the Tree has some elements in common with Narnia, but unlike the classic it is not as equally enjoyable for adults as it is for children. I personally would not read it again, but I think children would greatly enjoy the adventures the two friends experience together. There is a clear message to work with your strengths: Sebastian is very smart and Sara is very athletic and both come to appreciate their strengths more through their adventures. The reading level is more geared towards children, so it would be a perfect bedtime story or a book that children could read on their own.
Sebastian and Sara mistakenly descend into a mystical land where elves, mermaids, gnomes and other mythological creatures live. The two discover they have stumbled into an ancient battle between these fair folk and evil creatures called the Kylo. Their guide on this journey is Capri, an elf lord who is on a quest to find his lost tribe. The Kylo chase the children and Capri in his flying galleon north into the Arctic Circle where they find the most unlikely ally. During the final battle the children learn about sacrifice, love and ultimately forgiveness.