Sequence, granularity and taxonomy of learning objects are three open problems that will be faced in developing learning system. Concerning these problems and other ideas about educational technological standards and instructional design, the article mainly discusses the reusable strategies of learning objects. Firstly, based on discussing learning objects' characteristics, the article designs the learning object's content structure and programs learning objects' reusable administrative levels. Secondly, the article puts forward two sequence ways of learning objects. At last, the article descr...
