Laura Martin 
Glitch 

From the critically acclaimed author of Float comes a new whirlwind adventure about a pair of kids who must break all the rules of time travel, perfect for fans of Gordon Korman and John David Anderson. Regan Fitz and Elliot Mason have been enemies since they started training to become Glitcherspeople who travel through time to preserve important historical events. But everything changes when they find a letter from Regans future self, warning them about an impending disaster that threatens them and everyone they know.Will they be able to set aside their past in order to save the future?