I don't use set spaces for free play- if a toy is fought over, they get a warning and then they lose it. I do, however, use small mats in my classroom area where all of my learning activities are set up. If a child chooses an activity to use on the floor, then they have their own "work space". The other children learn to respect their friend's activities. This way they learn to share but also that some things are for one person only. I use my mats with early 2 year olds easily but I plan to use it with my new 18 month old too. We'll see how that works!