The objective of this study was to carry out methodical tests on the development of e-learning systems. Using the example of the e-learning system, "Information Systems in Dairy Farming", the interconnection of learning objects and learning contents was examined and a methodical selection and combination of learning theories was undertaken and tested to establish how the high quality of the contents and design of the system could be guaranteed, using an evaluation carried out concomitantly with the development of the project. Achieving these aims entailed selecting and testing appropriate evaluation methods. Since the development of e-learning contents involves a great deal of expense, it was imperative strictly to observe standards for ensuring that the contents could be reused and updated easily. A differentiated use of the learning objects was used in developing the e-learning system. The differentiation results from the varying importance of the types of knowledge. Text in combination with pictures, graphics and tables was primarily used for conveying factual and contextual knowledge. Methods and procedures were best conveyed by animations. With the help of the combination of the different learning objects, it was possible to design the e-learning system efficiently. The system development showed that the targeted use of learning objects geared to the type of knowledge to be conveyed led to an effective support of the learning process. Ensuring user acceptance and learning success is of great importance if an elearning system is to be used successfully. To that end, a continuous evaluation of the e-learning system was conducted concomitantly with the development. Following an analysis of the different evaluation methods, the heuristic method and the coaching method were selected for the expert test and the user test respectively. The methods of evaluation chosen proved to be extremely effective in identifying weak spots and are therefore also to be recommended for subsequent use. The evaluation was carried in several cycles, with both an expert test and a user test being carried out in succession in each of the cycles. These steps were repeated until the quality goals set by the project team had been attained. This evaluation thus proceeded iteratively, i.e. the results of the evaluation were fed back into the development process, with the changes based on that process then being reevaluated at a later point. The evaluation showed that by the end of the second evaluation phase the weak spots identified were of such a minor nature that it was no longer necessary to test the entire e-learning system in the third phase, but only a new, additional animation. After implementation of the theoretical and practical requirements and the completion of the third evaluation phase, it was possible to develop the e-learning system to the point where it could be put into use.