A spacing tool provides for the positive holding and spacing of structural members, such as 2. times. 4s, that is simple and easy to use and positively holds the structural members in place for nailing or fastening, while straightening any bows or twists therein. First and second jaw assemblies each include a pair of jaws extending from a first end thereof, the jaws of each pair being spaced from each other a fixed distance. A locking lever is disposed between the jaw assemblies second ends, and is pivotally mounted to the jaw assemblies to move them from a second, unlocked position wherein they are not in-line and the jaws are not spaced from each other a fixed, predetermined distance, to a first, locked position where they are substantially in-line and overlap and the jaws are spaced from each other a fixed predetermined distance to space structural members.