I have worked centers in my classroom in many different ways. I have had it more structured so each student went to a specific center at a specific time and eventually went to each center. I have also done it a little more free where the students can choose a center to work at as long as there is no more than 4 students at one center at a time. However, I am looking for a way that might kind of be a bit of both....not quite so structured, but not quite so free. It just gets to be too much to have 25 students switching centers at their leisure all the time!! So, please share how you run centers in your first grade classroom. Also, how often do you use centers?