Many of these activities need little or no preparation. (dice and deck of cards for math activities)
If you want more Substitute Activities check out these links at the Teaching Oasis.
Also check out Ms. Winston's book units under monthly resources. They make more great emergency sub. plans in a pinch.
One more thing we need 49 more followers to reach 100. When I reach 100 followers I will post a freebie on this blog.