Or if you have more than an hour block, once or twice a week you could have a half hour lesson with a center lesson based lesson following it. You could set the lessons for a month block and each week have a center day. That would be 4 different centers related to the current month and incorporating previous months' lessons. NOT a total of eight different centers. Each activity needs a specific academic goal.
Students keep a written account of what is accomplished.
Some center choices are changed twice a week. Others can be offered in a numbered sequence and are available at all times. Students receive Planning papers for recording their work. Behavior is recorded as is cooperation. Students who make good choices, stay on task, complete their work, and record what they have done will continue to work independently.