第 1 季，第 3 集: Zack and Rex really want to play in the Zerby Town sand pit. But the pit is so small they can't both fit on it at the same time. They decide to travel waaay down the forest trails to the natural sand pit and haul back some more sand to make it bigger. But after Rex dumps the first load, they realize it will take forever. Zack offers to help, but being just a little truck, rather than a dump truck, he finds that he can't carry sand that well. So Zack and Rex try, try again to find a faster way to make the sand pit bigger in Zerby Town. Zack finds Lily in the middle of the trail, trying to keep Zerbies from running over a flower. They try to come up with ways to protect the flower, while still keeping the trail open for Zerbies to drive through. Rex comes in to help by putting a rock in the middle of the path, but it still isn't the right solution. Soon Lily figures out a way to protect the flower on the road without slowing any Zerbies down. Axle, Zack and the Construction Zerbies set out to build the best jump ever. One that lets Axle jump high enough to go over a tree branch and far enough to go over a mud puddle. But they realize in order to build the shape of the jump just right, they’ll have to try, try again.