We've done a Round Robin and a Block Robin. For the Round Robin, make a center square for yourself at any size. Put the square and coordinating fabric in a bag. Those who participate stand in a circle and are assigned a number (to keep people in the same place of the circle month after month). Hand off the bag to the person on your right who adds to the block during the month. Next month, back into the circle in the same order and the bag is passed off to the next person. You end up with a medallion quilt. Some members were reluctant to add to an existing quilt because they were novice quilters. So for them we came up with the Block Robin. Put your choice of coordinating fabric in a bag and indicate what size block you want made. Same circle is set up as the Round Robin and the bag gets passed month after month and you get back blocks made for you out of your own choice of fabric. This can also be done as a row robin where the person who receives your bag makes a row (let's say 6 inch blocks by six of them, so 6x36). Make sure everyone labels their bag and make rules about (a) using ONLY the fabric in the bag or (b) you can add to the bag if you use another fabric and last but not least (don't make this mistake) make a list of everyone who is participating and their order in the circle. We lost a bag for a month last year - had one very unhappy member!