The sea is in many ways crucial for both people and environment. Indeed, the sea is a source of food and raw material, can be used as a transport route and affects the climate. Therefore, the sea is a fascinating and worth protecting biotope. The curriculum does not demand to teach the topic "sea" in regular lessons. It only occurs in the secondary school level I as an extracurricular topic. More precisely, it can be found in the eighth grade as a model for an ecosystem and can be used as an example of ecology and environment. However, at school the sea is often covered within the framework of a marine biology project week. In order to ensure the success of learning, it is necessary to include an extracurricular field trip to the sea in the regular lessons. That central condition forms the basis of this thesis. The basis of the teaching materials is an extensive didactic background. The developed teaching elements, which were produced for this thesis, should help teachers to embed marine biology weeks in the lessons. In order to make the teaching material as interesting as possible, it was important to use a wide range of various methods as well as different media. Additionally, the teaching elements were created with particular reference to different didactic principles (action and competence orientation, interdisciplinary learning). The teaching elements can be used in the fourth grade of secondary school level I as well as in courses or compulsory subject choices concerning secondary school level II. However, the main target group is the secondary school level I.In addition to the main emphasis of this thesis, which is the preparation of the teaching elements, parts of the collection were tested in different schools and evaluated by the pupils. The pupils' feedback should provide information about how the teaching elements are accepted by the students and where they still need to be improved.