How do you organize centers???

I have centers organized in a unique way.  First I take all the children's picture.  Then I make a little card with their picture and their name and laminate it. This is their ticket to go to centers.
  I place Library card pockets on the shelf where the centers are.  Lets say that I have a puzzle center and I only want 4 children to go to that center at a time.  Then I place 4 card pockets as shown in the picture.  The children place their "ticket" in the pocket.  When the pockets are full the centers are full.  If a fifth child wants to go to that center there are no more pockets for him so he must choose another center. 

This works so so well for center organization.  Studies show that when a child gets to choose their own center it is better, this way they choose the center but there is also a limit.  They learn to take turns and make choices.  It really works.

BTW--on the picture you can see some shoes, yes they are my feet with crocs on.