Explain how energy is conserved when you stop swinging on a swing

While you're swinging, your kinetic energy gradually leaks away because of your air resistance and friction in the connections up at the top where the swing hangs from.

Then, when you're ready to stop completely, you get rid of the rest of your kinetic energy by dragging your feet on the ground, and scattering sand, gravel, and dirt in every direction.

Either that, or else your Dad grabs the swing from behind and does a lot of negative work on it to take away its energy.

When you are swinging on a swing, the energy switches from kinetic energy to potential energy at a constant rate. When you are at the top of the swing before it goes down, the kinetic energy is 0 then converts to potential energy and vice versa. The total amount of energy stays the same when its stored and when its moving.

When you stop swinging on a swing, the kinetic energy must be 0 for you and the swing to totally stop. The air resistance is another possible factor here because the wind could affect how long and far you swing. Stopping by either dragging your feet on the ground or someone holding the swing back creates negative force to stop the swing.

Best of Luck!