Beasts of Olympus 5: Centaur School
Chiron the Centaur God has agreed to take Demon under his hooves and teach him what he knows about healing magical beasts. Being an apprentice healer is exciting, but Demon still needs to make sure the Stables are fresh and clean (the faintest whiff of manure and the goddesses will be on the warpath again.)
But with Arnie the grumpy Griffin suffering from feather drop and without his magical medicine box - Chiron has forbidden Demon to ask for its help as a first test of his healing skills - Demon is feeling the pressure. Not helped at all when Athene, Goddess of Wisdom, appears seeking help from Chiron. The world's only Phoenix has gone blind and it has lost its voice too. If it can't see to build its magical nest, and it can't sing the magical songs of renewal (both of which happen only once every hundred years), then the fire demons who the Phoenix guards will escape and burn up earth - and Olympus.
Chiron is nowhere to be found, so Demon must drop everything and take a trip with the goddess to the Mountains of Burning Sand. . .