We present a new approach called authoring by reuse to assist author during the design of SCORM like learning objects. It is now easy to design new learning objects by reusing existing ones connected together with dedicated operators. But the results are rarely satisfactory mainly due to their lack of consistency. In this paper we propose an assistance approach (i) providing indicators about the new designed learning object organized on three dimensions (complexity, reusability and pedagogy), (ii) computing metadata entries based on the information available about the reused learning objects and (iii) applying a rule based checking to ensure consistency.