My son is only 4 so we're no very formal at this point, but I'll answer anyway. We organize by seasons. His birthday is May 18th and between that day and the first day of Summer we take off from school and it is my yearly planning time. Each season is a new start and we incorporate learning to the seasons. For example, in winter we do sciences that are easy to do indoors. In the Spring we can learn about flowers and growing things from seeds and plant parts, etc. In the fall we can learn survival skills with camping trips. We take time off whenever we feel like it or there is a vacation opportunity.