Abstract
Modelling of objects of daily life is a topic which could be a motivating and fascinating access to mathematics education. For this reason the paper shows a possibility, how an object which is common to all students in school, the egg, can be an item for an exciting discussion in schools. Based on two mathematical definitions a figure is constructed. Based on those the description in polar-coordinates and Cartesian implicit equations is developed. This stepwise modelling cycle is shows the way how modelling of daily objects could be done in school and demands of curricula could be implemented.