A cover for a sandbox comprising a plurality of vertical poles situated around the perimeter of the sandbox and a cover assembly. The cover assembly comprises an outer frame, inner frame, and flexible cover. The inner frame comprises a plurality of support members, which support a flexible cover and are fixedly attached to the outer frame. Each vertical pole comprises a pulley system and a vertical slot. The pulley system is connected to the outer frame with an attachment means and is fully enclosed within the vertical pole except for a portion of the attachment means. The attachment means travels up and down within the vertical slot. Each vertical pole comprises a pole cover that is slightly shorter than the vertical slot and moves laterally to expose or conceal the vertical slot.