Demolition looms in the third Keepers of the School adventure from Andrew Clements, the master of the school story.

Benjamin Pratt is running out of time—and if the old Oakes School gets torn down by greedy developers, his hometown by the sea will be changed forever. Good thing Ben and Jill have found a secret weapon—a third Keeper. Who knew that a kid so annoying could be such a spy wiz?

But that nefarious janitor Lyman has secret weapons of his own: a bag of high-tech tricks, plus some low-tech security measures that are simple but terrifying. These kids are smart, but can they outsmart Lyman and his new “assistant”? There’s history in the making here, and the clock keeps tick, tick, ticking toward total demolition