The paper presents an alternative approach, based on infinitesimals, to calculus in secondary schools. Method was created as a part of the project OP PA Podpora vědy a přechodu na VŠ.
The presented method is based on the historical textbook of prof. ŠIMERKA. Method responds on situation in which calculus in no more a part of the compulsory curriculum.
The emphasis is given on clarity and understanding of all concepts.