If you define activity as movement, a child needs to move every 15 minutes to maintain their alertness (Jessica Hunt OTRL). We learn spatial concepts (up, down, across, left, right, etc) first with our bodies, then in building with blocks (3 dimensional) and finally on paper (two dimensional). Playground activity is critical for social skills (sharing, taking turns, etc.) as well as developing crucial muscles for maintaining a good posture at desks/tables, and good tactile (touch) and proprioceptive (body input through joints) for the little muscles of our hands for writing. Hope this helps. Please keep your children moving and playing!
Examples: Movement and exercise, interaction with piers, reading, writing, coloring, music, dance, centers, etc.
Kindergarten students need all of the above activities and more, in the classroom there will be plenty of activity to stimulate your little one's imagination and creativity, to keep them physically healthy and happy. Continue this at home and provide more activities that what has been introduced at school to expose them to as much as possible and to create a well balanced student.