The Sleeping King — Laurel Colless

Legend holds that in centuries past, a great king was laid to rest, leaving a promise to wake again when the world would need him most. Could eleven-year-old Peter Blue be that sleeping king? "He sleeps more than we do " complain the old people at the Gum Tree Rest Home in the Australian bush, where Peter has lived since his parents were killed by wildfire.
When a pesky wizard-type pulls Peter out of a nap, telling him to wake up and save the world, Peter isn't interested. It's only when a strange clue in his birthday treasure hunt leads him to Dad's Global Advanced Intelligence Agency (GAIA) jacket that Peter starts to change his mind. In the pocket, he finds a card for Spiral Hall--Secret School for the Ecodemically Gifted.
The Anthrog forces are rising on earth. They feed on the stench of human greed, and right now it's a free lunch. The Anthrogs also want to get to GAIA using Peter's high-tech jacket as the key. Can Peter get to GAIA before the Anthrogs get to him?
Peter Blue's legend-inspired story combines the magic of a child confronting a promise from another lifetime with the realism of climate change, which Peter and the initiates at Spiral Hall are destined to take on.