seesaw

Seesaw, also known as a teeter-totter in some countries, is a playground apparatus consisting of a long, rigid beam balanced on a central pivot. Seats are located at each end, and riders typically sit facing toward or away from each other. When one rider pushes off the ground, the opposite end rises and the other end descends, creating a repeated up-and-down motion.

Its operation follows the basic principle of a lever. The central pivot serves as the fulcrum, and the riders’ weights act as forces applied at equal distances from it. If the weights are balanced, the beam remains level; movement begins when one rider shifts position or applies force, causing the beam to rotate around the fulcrum. Friction, air resistance, and seat design influence the smoothness of motion. Some seesaws incorporate springs, curved seats, or additional fulcra to modify motion and safety.

Typical seesaws are made of wood or metal and may be anchored to the ground or mounted on a frame. A crossbeam supports the seats, and handles or grips provide stability for riders. Modern playground seesaws may have safety features such as rubber-tipped ends, wide seats, and soft landing surfaces; double-seesaw configurations and multi-seat versions exist in some parks and playgrounds.

The seesaw is a simple form of balance found in many cultures under various names. It has been a staple of playgrounds since the late 19th or early 20th century in many regions, though the basic concept is much older. Safety considerations emphasize supervision and appropriate surfacing to reduce injury risk.