Playing helps in refreshing their minds. It also replenishes the energy in the body. After studying for a few hours, playing won’t do badly to children. But unquestionably, I am totally against playing for long hours during the exams. Playing also helps in keeping the body well suited and full-of-life. After passing into the grown up stage the same people won’t find time to play in between their daily activities.
So allowing the children play for some time won’t do any harm.