A high-speed stacker preferably includes dual stacking arms configured to operate complementary to one another. Most preferably, an electronic control system is provided to enable precise control over the speed and positioning of the stacker arms in both horizontal and vertical orientations. Linear motion devices (such as hydraulic cylinders, screw drive linear actuators, or other devices) can be used to position the arms horizontally and vertically in response to instructions from the electronic control system. In operation, the electronic control system preferably controls the speed and ramping of the stacker arms to repeatedly move courses of material from a feed system to a stacking area at a rapid rate with little maintenance. The high-speed stacker can also be configured to operate fewer than all of the stacker arms to facilitate faster stacking of smaller courses of material.