The Carl-Friedrich-von-Siemens-Gymnasium is a grammar school undergoing a reconstruction process right now. In this way it reacts to social and school political changes influenceing both, the economic situation as well as the infrastructure of our area. Our institution is establishing a three-pillar-specialisation to better promote our students' strength and react to their special education needs. Therefore, the Carl-Friedrich-von-Siemens-school decided to become a whole-day-school. In the long run the school wants to offer a specialisation in three fields: in the bilingual and MINT-sector and in arts / literature. Our vision is that in the near future, students entering grade 7 and their parents can decide in which field they want to be promoted intensively.This reconstruction process is a huge challenge not only for the students and their parents but also for the teachers. In order to realize our long-term-goals we have introduced a bilingual and a MINT-module as well as one module for arts and literataure in all classes. Our teachers have realized an enormous professional training need in bilingual and MINT teaching. They are very motivated to put this reconstruction into practise but feel that they need more knowledge to opimize teaching and learning processes.When it comes to our whole-day-school system we are trying to find well-balanced school rhythms which are appropriate, harmonious and healthy at the same time. In this field, too, we are in a permanent optiminzation process. We develop ideas and methods to further develop our students' individual and independent learning processes.Therefore, we decided to define these three sectors: bilingual teaching, MINT and the whole-day-school system to be the prior teacher training focus at the Carl-Friedrich-von-Siemens-school. Our aim is to find on the one hand precise answers to questions we have collected in these fields and on the other hand to extend our experiences in these fields within the European context.We want to send six committed teachers who have already been very intensively involved in one of these three sectors to our formder Comenius-partner schools. These are the Dronninglund grammar school in Denmark, the St. James school in Exeter, Great Britain and the Lopez Neyra secondary school in Cordoba, Spain. Our project participants will attend lessons of different classes there, study their school curricula, get to know and analyze different test and examen forms and they will take part in conferences so that they will find answers to our questions and develop ideas that will be adapted to our specific school situation and needs.After the project abroad, the participants will be multiplicators and inform the teachers of their corresponding departments about their experiences and their results. After that, possibilities will be discussed how these could be adapted to our students and our school situation in a functional way. In this way not only the teachers who were sent abroad but all the teaching staff and hence especially our students will benefit from this teacher training program. We expect optimization possibilities in the whole-day-school system as well as enriching ideas how to build up a well functioning bilingual sector. Furthermore, we are keen on strengthening the MINT sector with cross-field projects within every day teaching and after-school workshops.The language skills of the participants should not be forgotten. Our project participants will improve their language skills which directly influences their teaching. Communicatin with our European partners will be more and more professional so that further European projects will benefit from this teacher training project as well.